8_factsheetsSince the last post, progress has been steady on the content upload and we’re now up to 8 factsheets in the new html based free resource section. I’m pleased to report that some of them have had a few hits too so it doesn’t feel like a wasted effort! Incidentally it’s been quite an experience reviewing some of the material. Although I wouldn’t say any of it is necessarily wrong, I don’t think I’d write things in the same way if I were to start from scratch and of the material that Helen wrote, although much of it helped shape my own coaching philosophy I do recognise that in more recent conversations with both Helen and Oli it’s become clear that there are more shades of grey than absolute certainty and labelling the material factsheets is perhaps a bit of a misnomer. ‘There is some evidence to suggest or generally tends to work in our experience’ sheets doesn’t quite have the same ring to it though!

Some of the content raised a few eyebrows on one of the UK message boards and it seems our decision to open up has been largely well received. It also raised an interesting debate over the nature of Sports Science and whether it’s actually any use at all. Here are a few thoughts I’ve been mulling over in the last few days.

One aspect of the debate stems from the lack of hard facts provided by sport science on seemingly trivial questions of training and performance enhancement. In an ideal world scientists could prove that intensity trumps volume, or that training for x hours at y% of your threshold will see you progress at the fastest rate but sadly things don’t work that way. If you want real certainty and irrefutable logic then become a mathematician, but be warned that the waters get a little murky around the edges in that field too...

So what use is sport science then if it can’t tell us the answers? The real strength comes from adopting the scientific method – a key tenet of which is “using a method of inquiry based on empirical and measurable evidence” (thank you Wikipedia). The human body is complex and the individual response to training is varied. Every type of training you do is experimental, there’s no way of knowing exactly what the response will be, but you can measure the effects. You’ll never know if doing something else might have had a better effect but by collecting data on the key performance markers you’ll certainly know when things aren’t working and make changes far quicker than if fumbling around in the dark without any measure of improvement. This is one reason that power meters have been truly revolutionary in the cycling world. It’s not just that they allow the collection of objective data, but that the data being collected is on such a critical factor in cycling performance – all else being equal more power equals more speed!

Road_to_successAnother argument is that people were racing very quickly in the past before sports scientists were on the scene and that’s undisputed. It’s often said that “success leaves a trail”. Well flip that on its head and I’d say failure often doesn’t leave a trail. With enough people participating in a given sport there are bound to be a few who having a natural gift for understanding what they need to succeed, or just being plain lucky that their chosen approach happened to be the correct one for them. What we don’t see is how many people got it completely wrong in these ‘golden days’. I’d argue that one of the key benefits of the scientific method is the speed with which errors are highlighted. In the absence of hard facts and certainty, the best we can do is minimise the time we spend up blind alleys and therefore increase the chance of eventually landing on the money. I’m sure this is one of the reasons behind the increased depth of competition across sport at all levels.

Now I’m not suggesting that athletic performance is purely a game of chance. The individuality concept can be overplayed – we are all similar in many regards and the general principles of training; specificity, overload, progression etc, all still apply and ensure that we’re not aiming blindly, and experience can identify characteristics in athletes that might encourage a certain approach. This is where art meets science and we begin to see real progress. Sports science is not a magic bullet that will provide the holy grail in athletic performance but a set of tools, or guiding principles that can help along the way. By no means definitive but just a few thoughts on where sports science sits within my own coaching philosophy at the moment...

And a slightly belated Happy New Year from all at PBscience :-)

Published in Blog
Saturday, 13 September 2014 20:54

Lab testing for cyclists


Lab testing for cyclists

Lab_test_ladyHow can the sport scientist help?

With the emergence of human civilizations came an interest in the importance and benefits of exercise.  Over 2000 years ago, Greek physicians wrote about the importance of proper nutrition on exercise performance.  Indeed, the first known written definition of exercise came from the Greek physician Galen (AD 131-201), who also wrote about the effects of exercise intensity, metabolism, and specificity of training on function. Over the centuries as medical research and technology has developed, so has research into the effects of exercise on the structure and function of the body.  In 1891 the first formal exercise physiology laboratory and accompanying university degree began at Harvard University in the USA. Since then the field of sport science has developed rapidly, with an ever growing number of athletes and their coaches looking to this discipline to unlock performance potential.

It is not uncommon for many athletes under the programme of a sport’s governing body to have both a coach and sport scientist informing preparation. The two roles can have a great deal of overlap, and indeed, some sport scientists hold the responsibility of the coach role too (you only have to look at British Cycling’s staffing to see this in practise). However, if we were to draw a distinction, the sport scientist is responsible for first profiling the athlete, and then, for piecing together what science can be brought to the situation to help maximise performance: whether this be training, nutrition, or performance strategies. The coach on the other hand is likely to be the provider of the training programme, and works with the athlete on a day to day basis. Normally, the sport scientist informs the athlete via the coach, helping with interpretation of training and performance data.

Performance testing

With the advent of power measuring devices, monitoring of progression on a regular basis is more easily done. The sport scientist and coach can look at training rides, tracking changes in heart rate alongside power output on a week by week basis. The field of sport science has been integral in developing performance trials, assessing how robust these measures are in truly tracking endurance fitness. For instance, asking a rider to perform ‘time trial’ efforts out on the road, with either a fixed distance or fixed time goal, provides a power profile, giving the coach parameters such as the ‘Functional Threshold Power’, ‘Critical Power’, and ‘Maximal Minute Power’. We will return to these tests another time, but for now, it is enough to understand that field testing does play an important part in an athlete’s training. Why? Since it allows updating of training intensities and also reassurance that the athlete’s training IS bringing about the desired changes in fitness.

What does laboratory testing bring beyond testing in the field?

Exercise testing in the laboratory brings an added dimension to the athlete’s preparation. Whether an elite athlete looking to shave seconds off a time or an amateur athlete who wants to set a new personal best, laboratory testing provides an in-depth look at how the body is functioning and adapting to the training regime.  Traditional coaching methods can look at performance outcomes such as time, power, distance etc.  However, this information does not explain the WHY behind achieving a certain performance – the science can measure both the input and output of the system.  Using sophisticated equipment and scientific methods, the sport scientist can evaluate the body’s physiological response to different stress levels under controlled conditions.  The ability of the body to perform any work depends on the precise coordination and efficient functioning of many internal (physiological) systems.  The body has the amazing ability to adapt very specifically to the stresses it endures.  As an athlete trains for a specific action or group of actions the body’s physiology will adapt, so that with time, the body can produce the greatest amount of work with the least amount of energy.  Although performance trials can track an athlete’s fitness changes, the only way to fully determine how the body is functioning internally is to conduct certain scientific tests in the laboratory.

Routine measures of physiology include those of oxygen uptake, ventilation, heart rate, blood lactate and glucose concentrations, oxygen saturation, and body temperature. These measures help the sport scientist evaluate the degree of stress the body is under: tracking how they change at set intensities (power in the case of cycling) can help inform the training process.

What are the direct benefits to the athlete and coach?

Visiting a sport science laboratory can be seen as a considerable investment, both in time and money. However, a thorough profiling of an athlete can bring greater performance gains compared to expensive equipment, at less than half the price! Here are some of the reasons to visit a sport scientist:

1. Setting training zones

Measuring aspects of an athlete’s physiology (such as oxygen utilization, blood lactate and oxygen saturation) over a range of exercise intensities allows an in-depth profile of the athlete’s fitness and ability. From this, more precise training zones can be deciphered, optimising the training stimulus presented. Setting of training zones relative to known ‘landmarks’ (such as the lactate threshold - LT, maximum oxygen uptake, VO2max) ensure the athlete targets the right physiology and achieves adequate overload. Quantification of training in this way also helps the coach and athlete safeguard against inappropriate loading and risks of overtraining. You can read more in our factsheet entitled the physiological basis of the training zones

2. Profiling of strengths and weaknesses

Analysis from data collected in the lab then allows a more precise and individualized training program to be developed, based on current physiology, and relative strengths / weaknesses. For example, from tests capturing the lactate threshold and VO2max, it is possible to see where these landmarks lie in relation to one another: an LT at a low percentage of VO2max might suggest the athlete needs more time training with quality endurance work.

3. Monitoring progression.

Perhaps the greatest benefit of regular lab testing is that the data collected allows the coach and athlete to monitor progression and accurately time peak race performance during the competitive season.  The physiological landmarks will move with training, so re-evaluation of training zones over time ensures optimal stimulus and adaptation.

4. Performance prediction.

Research in sport science has shown that laboratory testing is accurate in predicting race performance for endurance events1,2. As such, laboratory testing could be utilised to identify the type of event/distance for which an athlete is most suited and will be most successful. For example, a high second-threshold would indicate a good potential in time trialling, while a good maximal oxygen uptake could point more to individual pursuit ability on the track.

5. Develop pacing strategies.

With certain physiological landmarks correlating well to performance of a certain duration (for example, the ‘Maximal Lactate Steady State’ reflects the highest power sustainable for  an hour3), the sport scientist can advise the athlete on the most appropriate use of power output in a race: it isn’t simply about getting to a power and sitting there for an hour! With fluctuations in terrain and environmental factors such as headwind, knowledge of the power outputs sustainable for shorter periods whilst still allowing recovery enable pacing strategies to a very fine level of detail to be developed. Not all Watts are created equal!

6. Motivational aid.

As an athlete, seeing improvement is critical to help reinforce the training process. The job of a coach is made a lot easier if the athlete understands the rationale behind each training session, and that those sessions when joined together, have given an improvement. Certainly, measurement of the physiology in the lab also provides a level of detail that may not be picked up in performance trials out on the road. For example, oxygen cost at a particular power output (cycling efficiency) may change by 1% with a training intervention: only laboratory protocols and measurements are sensitive enough to pick up on this improvement. This tells us the training IS working, and merits continuing.

7. Helping inform nutritional strategies.

Proper nutrition is vital for optimal sports performance.  Lab testing allows analysis of the metabolic rate and accurate monitoring of energy expenditure. Again, taking the example of measuring oxygen uptake: from this data we can calculate not only the rate of energy expenditure, but also what percentage is given from carbohydrates and fats. This information can then be used to develop a nutritional program for optimised performance during training and racing.

Deciding on the test battery

Time in the laboratory is limited, and not every athlete wants to (or can afford to!) taper down for testing. Therefore, some choices might be needed in selecting which tests should be prioritised. The table below gives some indication of what types of tests the sport science laboratory can offer.

Test name What does the test involve? What will it tell me?
Lactate threshold test In order to detect the point at which blood lactate increases above baseline, a series of 3 minute stages at increasing work intensities are performed; each having a small fingertip sample taken at the end. The LT tells us the upper limit of exercise supported entirely by aerobic metabolism: it therefore also helps inform us when the athlete will switch from fat to carbohydrate utilisation.
Maximal Lactate Steady State (MLSS) This is the definitive test for the second lactate threshold, where blood lactate can no longer be held steady. This is defined in the lab using a series of 30 minute bouts of exercise. MLSS tells us the intensity an athlete could sustain for an hour without fatigue – prediction of 25 mile TT, or criterium race powers is therefore enabled.
Critical Power

A series of tests of either fixed time, or fixed distance during which the athlete does as much work as they can. The power you can sustain for a given time can therefore be determined, over a range of 3 to 30 minutes.

Determining CP can be very helpful for setting pacing strategies: as the protocol can assess both aerobic (CP) and anaerobic function in one testing protocol.
Maximum Oxygen Uptake (VO2max test) The definitive measure of aerobic function, at least in the traditional sense. The athlete is taken from a low intensity to their maximal over a ‘ramp’ lasting between 10 and 15 minutes (often, 25W per minute or 5W per 12s rates are used). The test also gives ‘Maximal Minute Power’. Although sub-maximal measures are in some ways more useful, the VO2max enables the ‘upper ceiling’ to be measured.
Efficiency In a constant power output test, oxygen uptake is measured in a ‘steady state’: normally done below LT to ensure no fatigue is taking place. The test takes no more than 10 minutes, and can precede a VO2max ramp test. Two athletes may have the same LT, MLSS and VO2max, but their performance could be different – why? Because they may each have a different ability to convert the oxygen to power – the so called “efficiency”. Useful information about fuel use can also come from this test.
All-out sprint test Several versions exist, but traditionally, 30s is used (the so called ‘Wingate’ test). The athlete is directed to go as hard as possible for the entire test. This short test enables peak power to be measured (within the first 5 pedal revolutions), and also the utilisation of the anaerobic work capacity over the entire 30s period.
Optimal cadence A series of all-out sprints, 5s in duration, at different cadences e.g. 50, 60, 70, 80, 90, 100, 110, 120, 130, 140 and 150rpm Drawing a graph of peak power against cadence gives a curve similar in shape to an “inverted U”. The peak in this “U” tells us the optimal cadence – very useful for track riders looking for the best gear selection.

Of course, it is possible to do a whole host of tests, the ones above are the more common available, and will probably form the core test battery for endurance athletes. It is possible to measure two or three of the parameters in one test visit.

Will I understand the results?

Initially the lab equipment and environment may seem a little intimidating and confusing.  However, the athlete is not expected to understand everything that is being done.  All the data will be analyzed by a professional sport scientist, and then compiled in an easy-to-understand report explaining what the results mean with regards to the current fitness levels and internal physiological status.  The coach would then be guided as to the type of training recommended based on the test data, helping them produce a training program based on the results and tailored to meet the athlete’s specific goals.  If the coach and sport scientist is one and the same, this is a very quick process! Those athletes without power measuring devices need not be concerned.  This equipment can be costly and is not always an option for many amateur athletes.  The training zones and program can be presented based on the equipment you have available.  A heart rate monitor is a low cost option for many athletes and training zones can be determined using heart rate as well as with power output data/running4.

How often do I need to be tested?

Testing needs to be carried out at regular intervals, as fitness levels and goals change throughout the competitive, pre-, and post-season.  Depending on the athlete’s goals, the coach and sport scientist would decide the most appropriate times to arrange the laboratory tests.  Regular analysis will allow progress and changes in physiology to be carefully monitored, allowing the training program to be adapted accordingly. This gives the best opportunity to achieve optimal performance. In an ideal world, an athlete might visit the lab 3 times per year:

  • At the beginning of winter training (to set training zones and a performance benchmark)
  • At the end of winter training, and 4 to 6 weeks pre-season (to assess the improvement in sub-maximal fitness and to evaluate how well the endurance base development has gone)
  • Mid season, perhaps during a lull in the race programme (and before a second peak is required late season)


  • The sport scientist and coach can work together to give the athlete the best chance of reaching their personal potential.
  • Laboratory testing is the most accurate way to monitor the internal and external workings of the entire body.
  • The learning experience gained from testing is invaluable in giving the ‘why’ to each training session. This can benefit athletes of all levels.
  • The testing identifies strengths and weaknesses in the physiology allowing the development of a comprehensive training program to meet specific needs and goals, allowing an individual to obtain his/her optimal performance.
  • Energy expenditure can be determined through lab testing allowing the development of an individual nutrition program to optimise race and training performance.
  • Laboratory testing can accurately predict race performance allowing athletes to monitor their progress and accurately time their peak performance.
  • Laboratory testing can determine the type of event and distance that an athlete is most suited for and at which he/she will be most successful.


1. Schabort et al. Med Sci Sports Exerc 1998, 30, 1744-1750.
2. Roecker et al. Med Sci Sports Exerc 1998,  30, 1552-1557.
3. Coyle et al. J Appl Physiol. 1988, 64, 2622-30.
4. Lucia et al. Med Sci Sports Exerc 2000, 32, 1777-1782.

Published in Free Factsheets
Saturday, 13 September 2014 20:51

What's so critical about critical power?


What's so critical about critical power?

The theory behind the Critical Power

The Critical Power (CP) concept was originally introduced in the 1960s by Monod and Scherrer1 in an attempt to improve the understanding of the work capacity of muscle groups. They noted a relationship between the amount of work that could be done and the time you could hold that work for. As any athlete will appreciate, at high intensities, you can only hold an effort for short periods of time; reduce the intensity, and you can sustain it for a lot longer. The nature of this relationship is explained by Helen in the following two videos:


The truth!

Whilst the mathematics pinpoints a critical intensity, in practice, CP appears to be too high to be sustainable. Typically, it sits at about 85 to 90% of VO2max, and it can be maintained for 20 to 30 minutes3. In fact, exercising at CP induces a lot of physiological changes such as an increasing blood lactate, heart rate and an oxygen uptake that rises towards maximum – nothing like the steady state it claims to be.

Why is this? A lot of research interest has been generated by this very question. In short, the Critical Power you get from the calculations depends on the protocol you use: factors such as trial length / intensity used to determine the shape of the curve, the number of trials used, whether you perform all trials in the same day or on different days, and even the type of maths you use to fit through the points.

So, how IS the CP best determined?

Researchers still cannot agree in which way the CP should be computed, which makes it difficult to interpret the findings with any certainty. But, generally we would recommend:

•    At least 3 trials should be used

•    Select intensities that will allow the athlete time to achieve VO2max / maximal heart rate and to exhaust within 3 to 15 minutes

•    Can be measured in one day as long as adequate rest is given between trials (3 to 4 hours)

Some sport scientists suggest the curve fitting can be enhanced using a measure of peak power too.

Why use the Critical Power?

If you’ve read our factsheet on ‘demystifying the lactate threshold’ you will be aware of the wide choice of ‘threshold’ phenomena there are out there to help you with guiding training and measuring fitness. Why do sport scientists want to offer you another one? Well, yes, the CP does fall in a similar area to that of the ‘second threshold’ group of parameters (such as MLSS, OBLA). The key difference is that CP is a lot more user friendly to measure. Firstly, all you need is the ability to measure your work (whether that

be a power measuring device, or a distance covered) and a stop watch - oh, and don’t forget the full bag of motivation! Compare this to all the sophisticated kit needed to analyse blood and respiratory responses. Also, to the competitive athlete, performing the trials to calculate CP are a lot more akin to racing – we call that ‘ecological validity’ i.e. the test actually measures what it says it does in the most valid of conditions.

You may find having an estimate of CP useful not only for estimating your performance ability and for tracking fitness across a season, but also because it might be a useful training intensity too. Research performed at the University of Brighton over the last 3 years has looked at exactly this issue4. It appears that training at and around CP improves fitness more effectively than training at the first lactate threshold, even when total work done is kept constant (so you have to train for less time at CP). Establishing the CP allows the coach to tailor training to your individual profile.

How can you estimate your CP?

Obviously, the laboratory remains the best way to assess physiological function in the most controlled manner. However, one of the benefits with the recent accessibility of power measuring devices in cycling is that it allows the rider and coach to perform fitness testing in the same environment as race performances. And, whilst field tests such as timed hill climbs or establishing maximum heart rates have been utilised for some time, the advantage of estimating the CP probably has more application to performance: given the intensity at which the CP falls and its relationship to race intensity. Follow this method to estimate your Critical Power:

•    Plan a day where you can set aside a session to measure your fitness – treat this day like a race day i.e. be well rested, hydrated, well fed etc

•    Establishing your CP can be incorporated into a steady ride of about 1.5 hours.

•    Select a route where you know you can ride for 12 minutes without interruption from traffic, junctions etc. It doesn’t have to be flat, but it will allow a more accurate representation of your power output / time relationship.

•    After a good warm-up, perform a series of blocks where the aim is to achieve as much work (i.e. go as fast as you can!) for that time period: a 3 minute, a 7 minute, and a 12 minute block.

•    It doesn’t matter the order you do them in: in fact, you may wish to swap them around if you do this test regularly.

•    Make sure you give yourself 15 to 20 minutes of easy riding in between each block. You won’t feel completely rested, so the CP you get from this method may be a little lower than if you did each block from fresh. BUT, it will be close enough, and the well within the error of testing and measurement.

•    To calculate CP, enter the average power and the time over which you tested in our online calculator.


The phrase ‘Critical Power’ has started to enter into coaching terminology – you may well come across some coaches who talk about a CP for a certain time period e.g. ‘CP180’ being the highest power you can sustain for 180 minutes. This is NOT the Critical Power concept! The CP is a single intensity calculated by looking at the ability to sustain different power outputs for different times.

Also, remember that the CP only uses trials causing exhaustion in 15 minutes or less. It is quite common, particularly in the running world, to take measured race times over given distances to estimate performance in another event. Whilst this uses the power (or distance in running) – time relationship, using durations above 20 minutes goes beyond the limits of the CP concept.

So, just be aware of this, and think about what it is you want to evaluate.


1.   Scherrer, J. & Monod, H. Journal de Physiologie 1960, 52, 420-501.

2.   Poole, D. C. et al. Ergonomics 1988, 31, 1265-1279.

3.   Brickley, G. et al.  Eur J Appl Physiol 2002, 88, 146-151.

4.   McGawley and co-authors. Unpublished PhD work (2009).

Published in Free Factsheets
Saturday, 13 September 2014 20:31



Periodisation for cyclists

For more information:

Dan's presentation on Approaches to Periodisation is worth a watch for more detail on the different approaches to periodisation and some of the practical considerations

Check out our factsheet on Goal Setting

Helen's talk on Winning in Cycling will help you set goals and plan for peak performance by going beyond the classical text book type material presented here

What is periodisation?

Periodisation is a planning process, taking into account the athlete’s major season objectives, and designing a training programme which enables the utilisation of correct loads and adequate regeneration periods for avoiding excessive fatigue. It thus serves as a useful tool for both athlete and coach. “Periodisation provides the structure for controlling the stress and regeneration that is essential for training improvements.”1

Periodisation enables a cyclic arrangement of training loads to increase the likelihood of performance excellence at a chosen time. Training load can be altered via interplays of volume, intensity and frequency (Figure below), optimising the training adaptations. Periodisation also encompasses changes in the basic structure of the training over time (e.g. low intensity steady training, high intensity interval training, recovery, and taper).

Periodisation methodology involves structuring the annual training plan in blocks or phases each of which focuses on the development of a specific energy system. The goal is to increase fitness steadily so to reach optimal fitness in time for their priority event or events. This implies a good understanding of the energy systems necessitated for the chosen event. This allows the decision as to the order in which the components should be developed (the periodisation), and how to develop each (the training), and know when they have been fully developed (monitoring training).


Some definitions2

Training intensity: Qualitative element of training. Can be expressed in absolute (speed, m.s-1; power, W) or relative terms (%VO2max; % of maximal heart rate).

Training volume: Quantitative element of training; total amount of training, calculated as a combination of duration and frequency of training.

Duration of training: The length of time a training session or a particular training programme lasts. The optimum duration will depend on the intensity of the session and the level of fitness of the individual.

Frequency of training: The number of times per week training is undertaken.

How do we “periodise”?

Prior to constructing your periodised training plan:

A] The first question to ask to yourself is “What is my ultimate goal?” Setting an aim to train for is the imperative first step. It is crucial to know what event you want to complete, when and where you want to peak to subsequently plan your training – too often people compete week in, week out for a whole season. “If you don’t know where you go, you might need a long time to get there!”. If you're not sure where to begin, read our factsheet on Goal Setting before coming back to this and if you want to go a little deeper with your goal setting have a watch of Helen's presentation on Winning in Cycling.

Setting your final destination will avoid a loss of motivation through lack of direction3. Over-competing often results in under-performing and under-training (significant stress from travel, social and psychological factors)4. Once your goal is defined, planning your training will help you organise your training year, months, weeks, sessions, and even sets. While the goal is your destination, the periodisation of your training becomes your journey! “Training tends to focus on the outcomes (winning) rather than the process (optimal training)1.

B] With the help of some sports science, you should define the factors that have been shown to explain performance for your particular event. With lab testing (lactate threshold test, critical power, VO2max test) your strengths and weaknesses can be identified and compared against the optimal. All that is left to do is to go out and train!


A] Duration and objectives of each cycle


The period from the start of the training plan to the “peak date” is divided into manageable phases, each phase being associated with a major objective (example: Preparatory, competitive, recovery phase). Some technical terms have been introduced in the literature to help athletes and coach to periodise training but unfortunately, their definition is inconsistent.

The first level of periodisation is usually called a macro cycle and can last 2 to 6 weeks5 (e.g. preparation phase, competitive phase). A good example is the phase of tapering which is well known to be difficult to program. Its purpose is to allow for fatigue to reduce while maintaining if not improving fitness before performance can peak 6 (see the factsheet on the training triad).
After having defined the main objectives of the macro cycles, each one can be divided in subsequent smaller phases called meso cycles, which also have predetermined training objective7 (according to the weaknesses / strengths you want to work on).
Finally, each meso cycle will contain several micro cycles, lasting from one session7 to a week6 (Figure left). A micro cycle can embrace 6 days of training and one day of rest, 5 and 2, 4 and 1, or 3 and 1.8 They can aim at stressing the body systems (shock and competition micro cycle) or can follow these stressing periods (recovery micro cycles).



Excessive load

Surpasses the capacity of the body and results in a form of overtraining

Trainable load

Results in a specific training effect

Maintenance load

Is sufficient to avoid a detraining effect

Recovery load

Favour promotion of the recovery process after a previous excessive or trainable load

Useless load

Is below the threshold to achieve any effects

B] Assigning training loads

Finally, training loads will be assigned to all the cycles included in the training period. Changes in training frequency, duration and intensity (Figure right) should occur in an appropriate manner for optimising training adaptations that meet your weaknesses and strengths. Length of each meso cycle, and changes in the training load will all depend on the type of adaptations the training is aimed at (metabolic, neural, etc). It would then be important to monitor the training responses to make sure the adaptations are maximal and the training impulse optimal.

An example of periodisation with an annual cycling training program for “Sam”

Here, we present a “classic” training plan to give you an idea of the first stage of the periodisation process. It has been designed for Sam, a cyclist aiming at performing better (2 minutes off a personal best) in a 25-mile time trial.

1. The transition phase/testing (2 - 8 weeks)

This phase (end of one season and beginning of the other) will give Sam time to reflect on his seasons’ successes and define goals for the next season with his coach. Sam will also be tested in the laboratory for a complete physiological screening (Lactate Threshold, critical power, body composition, maximum minute power). It is the best period to do so as Sam’s fitness is still high and “true” weaknesses and strengths will be defined and used in setting of training goals. His lactate threshold (47% VO2max) and economy[1] (11.6 were rather low compared to other physiological parameters measured9. Sam needs to improve them within the next 12 months in order to reach his goal. Active recovery, using cross training, is the exercise goal of this phase as well as possible rehab of aches, pains and injuries.

2. Preparation Phase (2 - 4 weeks)

Sam’s fitness will have slightly declined and he needs to get ready to build the aerobic base. Sam will start biking again but only at low intensity and a couple of times a week alongside cross and weight training.

3. Aerobic Base Phase (10 - 24 weeks)

This phase is always the longest because the aerobic system is the most important system to develop and needs a long time to develop. For Sam, the aerobic base phase is longer because his Lactate Threshold and economy are low. Sam will see his volume of training going from medium at the start to high volume toward the end, while the intensity will increase from a low level. Along with building the aerobic potential, Sam’s cycling workouts will also focus on cadence drills to improve his economy. This phase is complete when the aerobic system has been significantly developed. Signs of this include improvement of lactate threshold and VO2max, and ability to complete long rides.

4. Build Phase (8 - 12 weeks)

Efforts at and above lactate threshold are prioritized as well as maintaining aerobic power base. Some short highly intense efforts will be added to Sam’s program in order to stress more his anaerobic potential and increase the range of higher powers. Sam’s power at lactate threshold should improve, as well as his ability to maintain this power for longer durations. This phase should precede any peaking phase and be specific to the race goal.

5. Tapering Phase (2 - 6 weeks)

This phase is the most difficult to gauge; often, it takes a few attempts to individualise a taper. The fatigue accumulated over the last two periods should slowly disappear for Sam to reach his maximal potential on the date required. The time required to “recover” from previous weeks can be anything from 1 to 3 weeks depending on the level of fitness, workload accumulated over the past two phases, and individual “skill” in recovery. As Sam is unused to periodisation and has worked much harder than he is used to, the taper might be adjusted based on his feelings over the first. Volume is usually decreased while the intensity is maintained (if not increased) during a optimised taper but Sam’s feeling will be recorded and discussed in order to adjust the training load on a daily basis. Sam’s desire to race will be extremely high.

6. Race or Peak (2 - 6 weeks)

Peaks in performance are only held for limited time period unfortunately. Although individual differences are apparent, anecdotal evidence suggests absolute peaks in form cannot be held for much more than a week to 10 days. This makes it terribly difficult to peak for one event!

How do I know my training is going well?

You need to monitor your training to know whether it is going well and as well as you wanted to when programming it. Physiological testing in a laboratory will give you an indication as to how your fitness is improving in terms of aerobic and anaerobic potentials (lactate threshold, critical power, VO2max) as well as economy, flexibility, etc. But regularly recording and tracking your own progress are as important to get a good picture. A good training diary will help you or your coach adjust training. At PBscience, we make use of the Training Peaks online diary system to manage the training of our athletes. The amount of data generated by power meters, heart rate monitors and GPS units make some form of electronic storage essential and the Training Peaks system allows this to be stored alongside athlete comments on how they felt during the session, as well as other metrics such as body mass, hours and quality of sleep, nutrition etc. These days there's too much information to store every last detail in your memory, and the graphing and analysis features of software like Training Peaks allows the identification of trends in the data to done much more easily.

Why “periodise” your training?

The physiologist’s perspective

The effects of a given stimulus are only short term. It has been shown that a body cell put under a given stress will adapt in the short term but these adaptations will be limited in the long term. That is why an athlete will not get better if they always do the same training - the fitness would stagnate at a fixed level.

Some key training principles have to be considered for maximising training benefits. These are still under the scrutiny of scientists so it is difficult to find good scientific evidence so remain theoretical constructs. They are often referred as to “training principles”. For example, it is accepted that during a training phase, load should gradually increase to keep stressing the body (this refers to the principle of progression). This overload needs to be optimal, i.e. adequate stress/recovery balance, as opposed to maximal (to avoid overtraining).

The coach’s perspective

“When I started coaching with the U.S. Cycling Team, there was not much of an overriding structure to the team’s training… organizing training into blocks of similar workouts was one of the changes we made…When I was racing, the common training program was structured to hit all aspects of cycling every week. Monday was rest day, Tuesday was hill training, Wednesday was a long day, Thursday was for intervals and Friday was a short ride to rest up for racing or group rides on the weekend. The limit of that program was that there was never enough of a load on any one energy system to lead to significant growth. A full week was too long to wait…when we started restructuring training to tilt the balance to specific energy systems, the athletes made significant gains very quickly.” 11

The psychologist’s perspective

Planning assists in achieving regularity yet variation in the athlete lifestyle, decreasing the danger of monotony and mental saturation despite high training frequency. Planning in advance will enable you to gain in confidence in what to do and what for.



1.   Smith. Sports Med 2003, 33, 1103-1126.
2.   Kent. Oxford University Press, Oxford (2002).
3.   Williams et al. Human Performance 2000, 13, 159-180.
4.   Balyi. Elite athlete preparation: the training to compete and training to win stages of long-term athlete development. , in Sport Leadership, Coaching Association of Canada, Montreal (2002).
5.   bompa. Human Kinetics (1999).
6.   Mujika et al. Sports Med 2004, 34, 891-927.
7.   Matveyev. Progress Publishers, Moscow (1981).
8.   Viru. CRC Press Inc (1995).
9.   Coyle et al. J Appl Physiol 1988, 64, 2622-2630.
10. Armstrong et al. Rodale Press (2000).

11. Carmichael & Rutberg. Putnam Adult (2003).

Published in Free Factsheets
Saturday, 13 September 2014 20:20

Training in Zone 6


Training in zone 6 - VO2max intervals

Performance in endurance events is primarily limited by aerobic energy production i.e. energy being made available by the use of oxygen. Traditionally, the index of this ability is the maximal oxygen uptake, or VO2max. The VO2max is defined as the maximum rate that oxygen can be taken up from the ambient air and transported to and used by cells for respiration during physical activity. Check out our video of a VO2max ramp test to see how a sports scientist would measure this key parameter. It is the VO2max that describes the exercise intensity area of zone 6. This fact sheet explains why developing this ‘top end’ of your physiology can help your performance.

Why is ‘top end’ important?

For more information check out the following links

Training sessions for working in zone 6

VO2max test in the lab

Determinants of endurance performance

The physiological basis of the training zones

Setting your training zones

If you were to exercise at the intensity associated with your VO2max, you would typically last 4 to 8 minutes1. It would therefore make sense that in events lasting a similar duration (e.g. the 3 and 4km individual pursuit in cycling, or the 1500m in athletics), the VO2max would be the best predictor of performance. Indeed this is the case, with power outputs held in pursuits being very similar to ‘maximal minute power’ obtained in a ramp test. The time to exhaustion at maximum appears similar across different types of sports, but interestingly is inversely related to fitness2.

The relationship between VO2max and performance does extend down to less intense efforts too. Those events with durations of 30 minutes or less are still operating at high percentages of VO2max. Time trial cycling events (16km) and middle distance running events (10km) are run at ~ 90% of VO2max, and in fact, highly trained athletes appear to be quite stable at these high percentages of VO2max3,4. Some sport scientists argue that VO2max is the most important factor in dictating performance VO2, because it is the VO2max that sets the upper limit of VO2 at the race pace in events lasting one hour or so. Indeed, it is likely that a high fractional utilisation of VO2max is key because the higher you make your top end, the more likely that the rest of your profile is dragged up too. For example, consider a cyclist with a VO2max at 350W and a lactate threshold at 70% of this. If they worked specifically to improve VO2max power to 380W, they would likely also improve the LT by 20W (from 245 to 265. Furthermore, it is probable that there is some overlap in the mechanisms controlling both VO2max and high end race intensity. If a sport scientist observes an athlete with LT at a high % VO2max, they would likely suggest training to increase the ‘ceiling’.

What does limit VO2max?

Interest in the upper limit of aerobic fitness goes back to the work of Hill and Lupton in 1923, with research attempting to understand what controls VO2max ongoing ever since! Despite the amount of work performed, the exact mechanisms are still hotly debated by exercise physiologists. Essentially, the debate revolves around whether this upper limit is restricted by ‘peripheral’ or ‘central’ events in the body:

  • Peripheral: those aspects occurring at the muscle – number of capillaries, neuromuscular function, muscle fibre type, oxygen extraction capabilities. All these impact on the degree with which oxygen can be utilised by the muscle.
  • Central: factors within the central nervous system, and central circulation e.g. arousal, cardiac function, blood volume. All these impact on oxygen transport and the rate with which oxygen can be delivered to the muscle.

The figure below summarises these. It has been estimated that oxygen transport by the circulation controls 50% of the VO2max in exercise with large muscle groups5. As muscle mass decreases, peripheral factors such as the capillary blood flow and number of mitochondrial become more important as – so for the same person running and cycling, central factors might limit their running more than in cycling. It explains why cyclists often feel a VO2max test stops because of their legs!


How do we improve VO2max?

Like with any training aim, we must follow the principles of specificity. If, as the research suggests, VO2max is controlled by different mechanisms (e.g. central factors) to those in lower intensity exercise, it is important to stress the appropriate systems: in order to adapt, these systems must be stressed to a level to force re-modelling.

We know that VO2max is a product of the highest cardiac output (the amount of blood pumped around the body each minute) and the highest extraction of oxygen from this blood volume. Training to enhance either or both of these should lead to increases in VO2max. In a series of papers, Daussin and colleagues6, 7 looked at how these two products could be changed by training. In their first study, they found that interval training improved VO2max and cardiac output, more so than continuous, steady training of a similar total work. They concluded that interval training improves both central and peripheral components whereas continuous training was mainly associated with greater oxygen extraction. In their second study, they found the interval training more successful in changing the capacity of the muscle mitochondria to burn oxygen, yet capillary density was improved in interval work AND continuous training (in fact, to a greater extent in the latter mode).

Muscle fibre type changes do not appear to play a major role in VO2max enhancement in well trained individuals. This is mainly because the oxidative capacity of muscles far exceeds the cardiovascular systems’ ability to deliver the oxygen (i.e. increased rates of oxygen utilisation can always be instigated). However, working at VO2max intensities in training might recruit the fast twitch fibres preferentially. This would force them to become more oxidative, and add them to the muscle fibres usable in sustained, endurance events.

When would I choose to train the VO2max?

VO2max centred training is hard work, and will put great stress on the athlete’s system, so it is wise to consider when and how this training will be incorporated in the training year. You may use VO2max training in the following instances:

  • When looking to progressively increase VO2max to its maximum trainable limit over the many years of a runner’s competitive career. Several authors have suggested that athletes approaching their trainable limit for VO2max may even need to attain and maintain VO2max to elicit further increments8
  • After scheduled periods of low-intensity training and relatively low total training loads which have caused a transient decrease in VO2max (i.e. as part of a periodised training programme)
  • Peaking prior to competition when all physiological capacities are maximised to their trainable limit
  • After an absence from training due to a scheduled (holiday) or unscheduled lay-off (e.g. due to illness or injury). This training will lead to rapid improvements in form (if adequate base training has already been performed)
  • When decreasing the total amount of training time while still stimulating or maintaining a high level of cardiorespiratory fitness. Short bouts of training at and near VO2max may be effective in maintaining training during low training loads such as during tapering9

It is not recommended to start VO2max training without care and planning. Preparatory training should include several months of base training at intensities of 65–70% VO2max (zones 2 and 3) followed by transition training at 85% VO2max (zone 4)10.

What is the best training to do?

At the beginning of this factsheet, it was mentioned how the time to exhaustion (TTE) at VO2max is typically 4 to 8 minutes. This parameter has been used to optimise interval training sessions11, 12 – the idea being that athletes aim to increase the total time spent at VO2max in order to stress the appropriate systems as much as possible. When athletes perform high intensity intervals at the power associated with VO2max for 60% of the time to exhaustion, 40km TT performance and VO2peak increased (5% and 1% respectively)11. Using 60% of their own time to exhaustion gives an athlete enough time for the VO2 to ride to maximum in each interval – this is highly individual, as the speed of the oxygen uptake rise towards maximum levels may be longer or shorter than this: there is a need to decipher the time to reach VO2max for each athlete. Indeed, using a longer time to exhaustion (74%) is needed for some athletes to reach VO2max13.

So which is the best duration to use? Yes, using a higher % the TTE ensures VO2max is attained, BUT does it accumulate fatigue too rapidly? Perhaps it is better to extend the time spent at VO2max in the whole training session14 (i.e. the athlete can do more reps).


Intermittent protocols have been found to be more effective than continuous protocols for maximising the time spent at VO2max – that’s pretty obvious, just try to as much work as you can at your maximal minute power in one go, compared to splitting the work into 3-minute blocks! Research points to the work interval intensity ideally being between 90% and 105% of the VO2max, enabling ~3 min. in each interval12. There has been a lot of interest generated in using smaller durations than this. Comparison of 15s on/15s off interval running and 4 x 4 min of interval running (at 90-95% HRmax) found similar increases in VO2max over 8 weeks, both being better than moderate intensities15.  Recent research has even begun to consider the use of more intense, short duration repetitions.

What about the recovery?

As soon as you mention interval training, we have to factor not only the intensity and the duration of the effort, but also the recovery. Intervals to boost VO2max require the emphasis of ‘aerobic’ functioning:

  • Recovery needs to be long enough to facilitate recovery and enable greater accumulation of time spent at VO2max
  • Recovery duration too long: yes, a higher intensity could be attained BUT, bigger contribution to energy supply from anaerobic energy metabolism.

Most research suggests an equal work rest ratio to be optimal. In a recent study by Rozenek and colleagues16 selected physiological responses to short-duration (< or = 60 seconds) interval work performed at velocities corresponding to 100% of VO2max were characterised. The researchers compared 15s on/15 s off (15/15); 30/15; 60/15; and a TTE trial at 100% of VO2max. They found high intensity, short-duration 2:1 W/R intervals to produce responses that may benefit both aerobic and anaerobic energy system development, and thus recommended these for training.

Again, in keeping with the fact that the recovery period is to facilitate recovery, you need to make sure the intensity of the recovery is kept low enough. Some continuation of exercise rather than purely passive rest is recommended though, as this keeps blood flow higher.



1.   Billat & Koralsztein. Sports Med 1996, 22, 90-108.

2.   Billat et al. Ergonomics 1996, 39, 267-277.

3.   Perrey et al. Int J Sports Med 2003, 24, 138-143.

4.   Billat et al. Arch Physiol Biochem 1998, 106, 38-45.

5.   di Prampero. Eur J Appl Physiol 2003, 90, 420-429.

6.   Daussin et al. Am J Physiol Regul Integr Comp Physiol 2008, 295, R264-272.

7.   Daussin et al. Eur J Appl Physiol 2007, 101, 377-383.

8.   Billat. Sports Med 2001, 31, 75-90.

9.   Hickson et al. J Appl Physiol 1985, 58, 492-499.

10. Midgley et al. Sports Med 2006, 36, 117-132.

11. Laursen et al. Med Sci Sports Exerc 2002, 34, 1801-1807.

12. Billat et al. Eur J Appl Physiol 2000, 81, 188-196.

13. Laursen et al. Res Q Exerc Sport 2004, 75, 423-428.

14. Smith et al. Eur J Appl Physiol 2003, 89, 337-343.

15. Helgerud et al. Med Sci Sports Exerc 2007, 39, 665-671.

16. Rozenek et al. J Strength Cond Res 2007, 21, 188-192.

For more information check out the following links

Training sessions for working in zone 6

VO2max test in the lab

Determinants of endurance performance

The physiological basis of the training zones

Setting your training zones



Published in Free Factsheets
Saturday, 13 September 2014 20:15

Aerobic decoupling or cardiac drift


'Aerobic decoupling' or 'Cardiac drift'

The relationship between heart rate and power

With the increasing use of power meters by cyclists looking to monitor their training and racing, the heart rate monitor has taken a back seat in the minds of many athletes (and coaches). By choosing not to monitor heart rate alongside power, a large amount of information is being neglected that can have great value in guiding an athlete’s training. Some of the important concepts are outlined below.

One way to consider these ideas is to think of power being the input to the system and of heart rate being the output. In other words heart rate can be viewed as a measure of how much stress the body is under in order to meet the required work rate. Your heart rate response is very individual so the relationship between heart rate and power (power:HR)  is of little value on its own. However, when we begin to look at how this relationship changes over time it offers a fantastic insight to how you are responding to the training plan.

For more information check out the following links

Fitness versus endurance part 1

The importance of base training

Training in zone 2

Training in zone 3

Riding at a given intensity requires the body to use energy. For durations longer than around 60 seconds, the energy requirements are largely derived from aerobic sources, i.e. using oxygen. This oxygen is transported from the lungs to the working muscles in the blood, so the rate of oxygen supply is directly dependent on the rate of blood supply. This in turn is determined by the product of stroke volume and heart rate (stroke volume is the volume of blood pumped by each contraction of the heart). What we are doing by looking at heart rate at sub-maximal intensities is using it at as a ‘proxy’ for oxygen supply. This enables us to take some of what we learn in the laboratory and apply it to training in the ‘real world’. Of course this is subject to some significant assumptions (i.e. stroke volume being constant) – how these affect the power:HR relationship are examined below.much stress the body is under in order to meet the required work rate. Your heart rate response is very individual so the relationship between heart rate and power (power:HR)  is of little value on its own. However, when we begin to look at how this relationship changes over time it offers a fantastic insight to how you are responding to the training plan.

Changes during a single session

bike-with-srm-power-meter-by-KevinSaundersA common phenomenon for athletes training with a heart rate monitor is the gradual increase in heart rate as a session progresses, despite no increase in intensity. This is sometimes termed ‘Cardiovascular drift’. An often quoted mechanism for cardiovascular drift is the issue of heat and/or dehydration. In hot conditions (for instance training indoors) blood flow is increased to the skin to aid cooling. This extra blood flow is delivered by an increase in HR. Dehydration, which so often goes hand in hand with exercise in the heat, can add to this effect. Dehydration leads to drop in blood volume which ultimately leads to a reduction in stroke volume. As the heart is pumping less blood per contraction it must pump faster to deliver the same amount of blood, and therefore oxygen, to the muscles.

More useful, in terms of an athlete’s fitness, is the observation that changes in the power:HR relationship occur even without an increase in body temperature and in the absence of dehydration. This change in the power:HR relationship over a single session has been termed ‘decoupling’ and has been popularised by coaches such as Joe Friel as a measure of aerobic fitness. Your fitness does not change during an individual workout so it is perhaps not immediately obvious why the relationship should change over a relatively short space of time. For ease of explanation we will assume that you are producing a constant power and examine why the heart rate at that power might change. There is surprisingly little on this phenomenon in the sports science literature so there is ultimately a degree of speculation!

The mechanism behind this is related to oxygen demand. At the start of an endurance training session, the body selectively recruits the (predominantly slow twitch) muscle fibres that are most adapted to aerobic exercise. As these fibres fatigue, you are forced to recruit other fibres, including fast twitch fibres which are not as well adapted to aerobic exercise. In fact studies have shown that fast twitch fibres require approximately twice as much oxygen as slow twitch fibres for the same power output (Coyle, 1992). This extra oxygen requirement is delivered by an increase in heart rate.

Another cause of decoupling may be changes in the blood chemistry itself affecting oxygen delivery. Oxygen is carried in the blood by joining with a protein in red blood cells called haemoglobin. Under ‘normal’ conditions, haemoglobin is very efficient but during exercise, increased temperature, CO2 production, and acidity all have a negative effect on its efficiency. If the blood is less effective at carrying oxygen then more of it must be pumped to the muscles to meet the oxygen demand. Again this leads to an increase in heart rate.

Armed with this information it becomes clear that causing decoupling is an important training goal when looking to build endurance at certain parts of the season. The guiding principle of training is that we apply a stress to the body and then allow it to recover, grow stronger, and be better able to deal with the stress in future. Moderate decoupling is a sign that your slow twitch fibres have been sufficiently stressed and that the larger, less aerobically fit fibres are receiving some training stimulus. At the other end of the scale, excessive decoupling may point in the direction of too high of a training load. Analysing the amount of decoupling in your endurance training sessions can be an effective means of judging the training load and provide valuable insight into how well your endurance ‘base’ is progressing. Once you can complete a given workout with minimal signs of decoupling, it is time to increase the training load: either by adding to the length of the session or increasing the intensity.

Well trained endurance athletes will have minimal decoupling even in long duration workouts. In other words their heart rate for a given power will be the same (or very similar) at the end of a ride as it was at the beginning. This would be shown by a decoupling of less than around 5% - or in other words power and heart rate remain coupled. In fact when in top condition, it is possible to complete back to back rides of several hours in zone 3 with minimal decoupling!

How do we measure Decoupling?

Decoupling is normally measured as the percentage change between power:HR in the first half of the workout and power:HR in the second half of the workout. For example if you cycle for one hour at 200W with a HR of 150bpm and then cycle back for one hour at 200W with a HR of 160bpm then you would calculate your decoupling as:


Thankfully, this calculation is performed automatically in the Training Peaks WKO+ software! (see figure below)



Changes over a number of sessions

The power:HR relationship can also be useful in tracking changes in your condition over an extended period of time. Often changes in this relationship can be the first sign that it is time to update training zones. If over a number of sessions your power is higher than normal for a given heart rate, or your heart rate is lower for a given power, then it may be a sign that your fitness has improved. A difference in one session may not mean very much but if you see a consistent alteration in power:HR over a sequence of training rides, possibly accompanied by a decrease in effort levels at a given intensity, it might be time to ‘tweak’ your training zones. Alternatively for greater precision, this might be the perfect time to schedule a week of power profiling or a lab test.

Monitoring fatigue


In a similar way to showing changes in fitness, power:HR can also be used to monitor how tired you are. The use of HR monitors and power meters has enabled accurate tracking of training load through metrics such as Training Stress Score and TRIMPS but equally important for the working athlete is the effect of the ‘non-cycling’ stressors in your life. The quality and duration of sleep, stress at work and in relationships, and nutritional choices amongst others all have an effect on how well you adapt to training and how fatigued you are at any point in time. Analysing your training load alone may suggest that you should be fine to complete the days prescribed training session. However other factors in your life may mean otherwise. An athlete needs to consider ‘total stress’.

Changes in your power:HR relationship can help to measure this fatigue. To confuse issues, for a given power, heart rate may be higher, or vice versa, lower than normal when tired. When the body is under stress, a number of hormones (such as cortisol) are elevated and can affect your heart rate response. Take a look at your power:HR relationship in the warm up to your training session. Is it within a normal range for what you would expect? If not consider other factors that might influence your heart rate – is the temperature particularly hot/cold? How do you feel? If you are sore, lethargic or the power target requires a greater effort than expected AND your power:HR is different then take it as a sign that you are inadequately recovered and consider whether it might be wise to abandon the training session or just have an easy recovery spin. Ultimately the aim of training is to stress your body to adapt and become stronger but there comes a point where extra training will just make your more tired rather than more fit. Use power:HR as a tool to help identify this point and prevent the need for an extended period of recovery.


For more information check out the following links

Fitness versus endurance

The importance of base training

Training in zone 2

Training in zone 3

While it is true that heart rate is affected by many external factors that limit its effectiveness in monitoring training intensity, when combined with the use of a power meter it becomes a very powerful tool. Used with other information such as your rating of perceived exertion (RPE) for each session it can provide valuable information on how well your endurance is developed, the first signs of improvement in your training zones and an indicator of your fatigue levels on a day to day basis.

None of this is possible unless you remember to wear your heart rate strap for EVERY session and make detailed comments in your training diary on how the session felt!


Published in Free Factsheets
Saturday, 13 September 2014 20:06

The performance triad


The performance triad

The concept of a “performance triad”: Training, recovery, nutrition

Being fit and not fatigued is what an athlete requires to hit peak form and surpass his/her performance at key competitions1. Peaking requires the psychological and physiological levels to be at their highest, and fatigue to be at its lowest. The difference between the two extremes has to be maximised for the day of the major competition.

Physical training increases fitness, but also brings with it fatigue, hence the need for body and mind to recover from training. An appropriate supply of nutrients will optimise the bodily adaptations induced by the training and allowed by resting periods. Recovery and nutrition facilitate the management of fatigue. In order to improve, an athlete must consider all 3 aspects in equal measure……read that again – EQUAL measure. One is NOT more important than any other.


Physical conditioning… Train!

The principles of training have been introduced in order to help coaches providing efficient training programs. They include the principles of individuality [1], specificity [2], progressive overload [3], periodisation [4], and disuse [5]. Recovery is another training principle further discussed below.

[1] INDIVIDUALITY: First of all, any training program must take into account the specific need and abilities of the individuals for whom it is designed. This is why within the first period of a training program, a physiological profile of the athlete needs to be drawn, from which strengths and weaknesses will be depicted and worked upon (see periodisation). Heredity plays a major part in determining how a person responds to a training program, therefore no two individuals (with the possible exception of identical twins) will respond in the same way to a given training program3. The individual variations in body adaptations will explain why some athletes show great improvement after participating in a given program (responders) while others experience little or no change after following the same program (non-responders).

Profiles of athletes tested in a laboratory have to be compared against “gold standard” profiles corresponding to their particular event. [An example of key components explaining endurance performance is given in the fact sheets “Determinants of endurance”]. Likewise, it is possible to depict strengths and weaknesses of a particular athlete for a particular event, to then decide on the main objectives the training should aim for (reinforcing strengths? Improving weaknesses?), and train specifically toward these objectives.

[2] SPECIFICITY: “To improve a particular component of the physiological profile, it has long been recognized that the training must emphasize that component in training3. Achieving specific training adaptations will be possible thanks to appropriate training and will lead to improvement in the target key component of performance. Monitoring training using rigorous scientific testing will be essential at this stage to control the way the athlete copes with, and adapts to, his training. Interestingly, the principle of specificity doesn’t refer to the intensity but stimulus / stress the body is put under during the training.

From the principle of specificity, we understand that training at intensities close to the ones used in competition is the optimal way of improving the key physiological factors associated with that particular performance. For example, training around lactate threshold would enhance lactate threshold. However, it is surprising that we can improve some components of a physiological profile by training at intensities that these components would not be necessary intuitively associated with4. A recent study5 has demonstrated this key aspect of specificity in the training stimulus (as opposed to training intensity). It shows that physiological adaptations following very high intensity training induces greater improvement in the aerobic components of fitness (VO2max, lactate threshold) than previously thought5.

[3] PROGRESSIVE OVERLOAD: Now the training has been designed according to the principles of individuality and specificity, periodisation must include overload and progression to be successful. “The body must be overloaded so that it has to work harder than normal3. All is about “progressively pushing your limits”. The process of periodisation will give a framework of progressive overload to be structured over time.

[4] PERIODISATION: To be “shaped” and enable a peak at the key event, a training period of 6 to 12 months (up to 4 years for an Olympic athlete) in preparation for the ultimate date needs to be organised. The major objective of periodisation is to program the time frame of various training stimuli the body will be put under during training1. The training stimulus can be a single training session, a given training week, or even a period of several weeks. Consequently, the stress the body will be put under, is specific, but pre-anticipated psychological and physiological adaptations will occur.

A progressive overload will help to MAXIMISE THE BENEFITS OF TRAINING. The periods of training have to include sufficient periods of recovery for the body (and mind) to adapt to the training load. We now know for example, that training hard each day at high intensities or for long duration, or both, will lead to body mal-adaptations because too little variation is assigned to the total volume of training.

[5] REVERSIBILITY: A break from training will induce a gradual lost in the training effects: “Use it or lose it”… This needs to be considered during the period in-between two seasons, as well as when an injury limits the training that can be / was prescribed. Strategies to limit the loss of fitness (“maintenance plan”) can be put in place according to the circumstances and the original training plan (cross-training, strength-training).

So, to summarise – training is simply the act of taking the body to a new level of functioning: taking it out of its comfort zone (so to speak) and causing it to change – in anticipation of more hard work ahead. The principles of training above make sure that the rate and suitability of training allows stress to be imparted without over straining and consequent breakdown.


Recovery is the most under-rated aspect of training. It is actually a major principle of training3, “which posits that adaptation takes place during the recovery period after training is completed3. Even coaches who understand its importance can find it hard to prescribe rest during or following training sessions as well as following periods of hard training (a couple of days, weeks – see periodisation). However, recovery is vital for adaptations to occur. To perform throughout the season at peak levels, your muscle must be able to recover and repair themselves after each hard effort. That means putting as much effort into your recovery as you do in your riding.

How can recovery be more important than the training?

Recovery is required for the repair of damage to the body caused by training or competition. It includes changes within the muscles alongside a re-balance if not enhancement of the hormonal functions and immune defenses. During recovery, muscles for instance should repair their structure, if not increasing in size (protein build), at least replenishing their energy stores: all these changes enhance the athlete’s physiological potential. Long-term adaptations to training are generated by the cumulative effects of the transient events following exercise bouts2.

The decrease in fatigue with good recovery, alongside the fitness enhancement given by training, will lead to performance gain1.  This phase of improvement in overall form is often called supercompensation (Figure 2). It means that a correct balance between the training stimulus and recovery is essential for an overshoot in performance to occur (Figure 2, Panel A). When the frequency of the training stimuli is too high, the training stimulus too strong, and/or the recovery too short, the fitness level can decrease leading possibly to overreaching or overtraining (Figure 2, Panel).

Figure 2: Principle of supercompensation


It is all about pushing optimally - as opposed to maximally. A fine line! Sport scientists always seek ways of monitoring this fatigue/fitness balance, such as the use of heart rate variability.

“I am fit enough to cope with my training. I don’t need any kind of recovery!” … Wrong!

The nature and duration of the recovery will depend on the type of training being performed, the level and nature of the overload, and the level of fitness of the athlete but every individual has to take a rest.

Recovery can vary in nature, going from complete rest, to easy training sessions – although it is debatable that if you are prioritizing recovery, why exercise at all! Nutrition will be essential to speed up the recovery process and make sure you get ready for the next training session. Good-quality, long sleep will give time to your body to recharge its batteries, all the energies usually reserved for performing daily tasks being dedicated to the self-reparation of the body. Self massage and stretching are also popular with athletes, although most support for these tends to be anecdotal.



The choice of recovery time is also dependent on the aim of the training being performed as well as the level of fitness of the athlete. Fitter athletes tend to recovery quicker  (Table 1) Sport scientists are still studying the speed of recovery and body adaptations following training to better define the recovery time needed after particular sets of training.

As recovery is an inherent aspect of training, some nutritional strategies can speed up the rate of recovery, as well as maximizing physiological adaptations to training. Good nutrition is crucial for high peaks of form. Sports scientists are now trying to understand how exercise and diet affect genes and protein expression within the muscle6 as the genes alterations explain changes in our physiological potential… so dietary intervention, alongside physical training, is considered to have a massive impact on cellular adaptations2 (Table 2).

Table 2: Post-exercise recovery: What to consider?


Eating well to promote training adaptations

“It is better to prevent than cure” Fuelling during training will enable to exercise for longer, especially at intensities around lactate threshold and critical power. At lower intensities, the energy is mainly supplied by the utilization of lipids, the contribution of the carbohydrates increasing with increasing intensity. But the utilization of lipids to produce energy during exercise requires the burning of carbohydrate as well, hence the massive need for carbohydrate whatever the intensity.

Without any carbohydrate, you just stop!” So, since carbohydrates play a predominant role in the performance of prolonged exercise2, its provision during exercise enables more work to be done, and therefore more stress for the whole body (consequently greater adaptations).

Don’t forget, water is the most essential ingredient to a healthy life. Water has many important functions in the body including transportation of nutrients, elimination of waste products, lubricating joints and tissues, temperature regulation through sweating, Facilitating digestion.

Proper hydration is especially important during exercise as dehydration impairs performance as well as training adaptations (muscle cramps, dizziness, fatigue, heat exhaustion, heat stroke). Adequate fluid intake for athletes is essential. The longer and more intensely you exercise, the more important it is to drink the right kind of fluids. Studies have found that a loss of >2% of one's body weight due to sweating is linked to a drop in blood volume, the heart having to work harder (higher heart rate) to move blood through the body.

Monitoring urine volume output and colour[1] and weighing yourself before and after exercise[2] are useful gauges of hydration level.

Alongside dietary intake during training, an appropriate diet during the training period (long-term) will also increase the impact of training on the muscular adaptations2. For example, it has long been recognized that there is a close association between dietary carbohydrate intake, muscle glycogen concentration, and endurance capacity2. For this reason, it is recommended that individuals training for sports in which carbohydrate is the most heavily metabolized fuel should consume a diet rich in carbohydrate (endurance sports). Another strategy that might enhance the training adaptation would be to utilize an alternative fuel source to carbohydrate and/or to slow its normal rate of utilization during exercise. Such a fuel is fat and the effects of fat supplementation during one or several training sessions on exercise performance has gained recent attention2. Protein availability is critical for optimizing many of the adaptations that take place in muscle in response to both endurance and resistance training. The main determinants of an athlete’s protein needs are their training regimen and habitual nutrient intake. However, the optimal amount of protein required by athletes to enhance training adaptation is unclear2 (~1 to 2 grams per kilo of body weight per day; 1 grams being the recommended quantity for the general population). Fortunately, most athletes consume sufficient protein to accommodate even the highest estimates of protein needs.

Eating well to hasten recovery from training

The quantity of intake has to match what the body needs to recover quickly. The need for carbohydrates, proteins, electrolytes, free-radicals, amino-acids, is not the same following all sessions (Table 2). For example, both type and amount of fuels being burned during exercise are dependent on the intensity and the duration of the training set. Of course, what you have been taking during the exercise would need to be considered for the dosage of post-exercise intake. Muscle energy reserves would have to be sustained if not enhanced for further training sessions to be performed.

The sweating rate will also be affected by the environmental conditions (heat, humidity), hence the need of taking these environmental conditions into account when offsetting the electrolytes misbalance caused by training. When you sweat, you lose more than just body water! Free-radicals are produced during strenuous exercise and carry a potentially damaging side effect of training hard. Free radicals have been associated with muscle soreness and in some cases, even tissue damage. The key to stopping free radicals is a good intake of antioxidants like vitamin C, vitamin E, and beta-carotene. Fortunately, most healthy athletes generally eat enough anti-oxidant rich foods like fruits and vegetables to keep their muscles in good repair.

There are also specific windows of time after a workout is over for food and drinks to be intake so that replenishment is maximized. For example, replenishment of glycogen stores via carbohydrates-rich foods and drinks should be prioritized in the first 15 to 30-min after exercise. It has been shown that during this window, the enzymes responsible for making glycogen are the most active, so you can replenish your store quickly during this time. For even faster recovery, adding a little protein[3] will stimulate the action of insulin – a hormone that helps transporting glucose from the blood to the muscles –enhancing glycogen replacement in the muscle. It has been shown that ingesting a mixture of carbohydrate and protein before or immediately after completion of a training session indeed increases the synthesis of protein and decreases their breakdown usually observed post-exercise2. Protein also helps repair broken-down muscle tissue, so you feel stronger quickly. Protein ingestion immediately post exercise also appears to have the greatest potential impact on training adaptations2.

[1] A large amount of light colored, diluted urine probably means you are hydrated; dark colored, concentrated urine probably means you are dehydrated.

[2] Any weight lost is likely from fluid, so try to drink enough to replenish those losses. Any weight gain could mean you are drinking more than you need. 1 kg = 1 L

[3] 1 gram of protein for every 3 to 4 grams of carbohydrates in your recovery meal.



1.             Smith.Sports Med 2003, 33, 1103-1126.

2.             Kent. Oxford University Press: Oxford, 2002.

3.             Hawley. J Physiol 2008, 586, 1-2.

4.             Burgomaster et al. J Appl physiol 2008, 151-160.

5.             Hawley et al. Sports Sci 2006, 24, 709-721.

6.             Hargreaves & Cameron-Smith. Med Sci Sports Exerc 2002, 34, 1505-1508.

Table 1: How much recovery time do you need?

You need

I you spend

8 hours

0 to 6 hours below lactate threshold

8 to 10 hours

30 to 60 min at lactate threshold

24 to 36 hours

75 to 120 min at lactate threshold

24 hours

15 to 45 min at critical power

24 to 36 hours

60 to 90 min between lactate threshold and critical power

24 to 36 hours

10 to 30 min above critical power

36 to 48 hours

45 min or more above critical power

Published in Free Factsheets
Saturday, 13 September 2014 17:10

Train low, race high


Fasted rides: train "low", race "high"

Ask any athlete about training and nutrition, and most would repeat the same message – you need to make sure your energy stores are topped up in order to make the most of your training sessions. Right? Maybe not! Recent research, from a number of groups, suggests that training ‘on empty’ may actually be beneficial, flying in the face of conventional wisdom.

Muscle glycogen stores are essential for maintaining high intensity exercise. Typically, the body stores around 300 to 400g of carbohydrate in this form - that’s about 1600kcal of readily available energy (or 3 hours of good paced exercise).  Carbohydrate ‘loading’ can enhance exercise performance by allowing the athlete to race at their optimal pace for a longer period before fatiguing. Most of the research in this area quite simply stated suggests athletes should maintain high carbohydrates diets (10g per kilo of body weight per day), with particular care taken to post exercise nutrition. The market is swamped with industry claims about ‘recovery products’: companies waxing lyrical about ideal mixes of carbohydrates; additions of protein; protein types impacting on absorption rates – all of which necessitate the athlete to take in the product within the first 20 minutes after exercise. More detail on glycogen repletion strategies can be found in another of our PBscience factsheets.

So, what’s changed?

Low_glycogen_chartRecent research looking at how an athlete’s nutrition interacts with the body’s genes ‘switching’ on and off (which promotes muscle adaptations to training) has suggested that training with low or moderate glycogen levels may accelerate the transcription of several important genes. In one study involving 7 untrained volunteers1, greater increases in muscle enzyme content and exercise endurance were seen when training was performed with lower muscle glycogen stores. In a very elegant experimental design, the volunteers trained one leg twice a day, followed next day by rest. The other leg did the same training volume, but spread across two days. The research group reported that performance at 90% of maximum (~ 10 mile time trial intensity) improved significantly after 3 weeks of training in both legs – but, more remarkably, the ‘LOW’ glycogen leg (which had been training twice a day) improved by almost twice as much!

How does ‘training low’ affect the body’s systems?

Hansen and colleagues, the authors of this study, also took muscle biopsies from both legs, and were therefore able to measure the content of key enzymes involved in exercise metabolism. Their measurements in the LOW leg included:

  • Increased concentrations of enzymes key to oxidation and energy production;
  • Increased mitochondria, the power houses of the muscle tissue;
  • Increased concentrations of the stress hormones adrenalin and noradrenalin.

It would appear that depleting the muscle glycogen stores acts like a ‘cellular signal’ switching on genes that in turn, change the production of proteins in the cell. One affected protein is an enzyme called ‘AMP activated protein kinase’ or AMPK, which when activated, encourages the build-up of mitochondria within the muscles.  The greater the AMPK activation, the more mitochondria, and that results in a greater capacity for producing aerobic energy – possibly explaining the greater endurance ability. Having more mitochondria will help an athlete to be more efficient at burning fat: since this process relies predominantly on using oxygen. The hormone response was also interesting - training on low glycogen puts the body under extra stress, meaning it produces more adrenaline. Therefore the body adapts to dampen the body’s response to adrenaline. This hormone is strongly linked to lactic acid production – if the body is less sensitive to the adrenalin’s effect, we might see lowered lactic acid production which in turn helps to increase the lactate threshold to a higher intensity.

Does this mean I should throw away the sports recovery drinks?

It’s too early to be sure that this practice will help the performing athlete. A study just published2 wanted to make the research more applicable to the sporting scenario. It criticized the original work of Hansen and colleagues because:

  • The data was collected on untrained volunteers;
  • The mode of exercise (leg extension performance) was not relevant to athletes;
  • The 3 weeks of training was ‘clamped’ at a set intensity – in fact, it remained at 70% of max for an hour for every session;
  • Athletes are more likely to train using a variety of session types (steady work AND intervals);
  • The majority of athletes are reluctant to take a lot of rest days, making this type of training protocol unlikely;

In the study of Yeo and co-workers2, they designed a study which they view as having more ‘ecological validity’ (where what is done in the lab reflects true life practice in the field). They asked 18, endurance trained cyclists / triathletes to perform 3 weeks of training. Two groups were set up:

  1. HIGH group – trained 6 days per week, alternating sessions of one hour at 70% VO2peak with an 8 x 5 minute interval session;
  2. LOW group – trained twice per day, every second day using the same sessions as the HIGH group (with a 2 hour rest between).

The intervals consisted of the athletes going as hard as they could to maintain 5 minutes of high intensity training. This kind of ‘HIT’ has been shown to be a very effective training session3 and more importantly for this study, to deplete 50% of carbohydrate stores. Both groups were fed the same diet (8-9 per day of carbohydrate) to make sure that glycogen stores would only differ due to the training regimens. After the training, performance was monitored by asking the groups to ride for 60 min at 70% VO2max, and then to ride a 1 hour trial, sustaining the highest power they could. This second hour would be akin to a 25 mile time trial effort, or a 10 mile running race.Chaingang

The results, perhaps a bit more applicable to the athlete population than Hansen’s original paper, demonstrated some similar findings: Fat oxidation tended to be higher in the performance trial in the LOW group and the muscle enzymes involved in oxygen requiring energy processes increased more in the LOW group than in HIGH.

However, unlike in the Hansen paper, there was NO difference in the performance trial improvements between the two groups. What is worth noting here is that the HIGH group trained at a higher intensity during the HIT session: undoubtedly, this is a key finding of this paper – even with the metabolic effects of ‘training low’, without glycogen, training quality may be compromised.

A really interesting finding from this study was that already trained athletes had their glycogen levels FURTHER enhanced – the LOW group had significantly higher resting glycogen when measured after the training regimen. The authors linked the enzyme adaptation to this glycogen response: frequent fluctuations in low, high glycogen may have disturbed the body’s homeostasis (its internal thermostat) causing the gene switching to occur.

Practical implications

There is still a lot of interest in the sport science community how depletion of glycogen may change the way the body switches genes on and off after exercise, and the accumulative effect of this on fitness. However, it is too early for coaches to recommend this regimen to the training athlete. It is worth considering these points:

  • Training with low glycogen stores may lead to immune system suppression and the increased likelihood of falling ill.
  • Training intensity appears to be compromised when you have to train twice a day, on low muscle glycogen stores.
  • Although this novel research may prove to bear fruit during training, it is not a practice advised for athletes before competition: in other words, always “race high”!

However, since the training effects in the most recent study of Yeo and colleagues appear to be at least equal with and without sufficient glycogen stores, training twice a day MAY be a useful strategy for athletes with restricted time for training. This would make the nutrition on the intervening rest day critical. It might also be that the coach and athlete could specify times in the training year where small, intense blocks of this work are completed – the aim to be increased fat burning, NOT to increase power outputs around race intensity (e.g. early on in the periodised year).

So, for now, don’t throw away your protein recovery drinks!



1.   Hansen et al. J Appl Physiol 2005, 98, 93-99.

2.   Yeo et al. J Appl Physiol 2008, 105, 1462-1470.

3.   Lindsay et al. Med Sci Sports Exerc 1996, 28, 1427-1434.

Published in Free Factsheets
Friday, 12 September 2014 15:52

Training in Zone 2


Training in Zone 2: building the base

What is ‘Zone 2’?

Zone 2 is the training intensity used to bring enhanced general aerobic fitness. It is training that is often associated with the phrase ‘building the base’. Without full development of this base, the rest of the training an athlete does has a very fragile foundation. Indeed, training in Zone 2 gives you the ability to withstand higher training loads (volume and intensity).

The upper boundary of Zone 2 is the ‘lactate threshold’. This is the first threshold, where blood lactate first starts to increase away from resting levels. Typically, this zone occurs between 55 and 70% of an athletes’ VO2max. The best way to identify your own lactate threshold is to visit a sports science laboratory, Dr Helen Carter explains the protocol for a lactate threshold test in this video. Alternatively, you can approximate your training zones with a simple field test, using either your heart rate monitor and/or your power meter.

Why should we use Zone 2 training?


Training in Zone 2 is important to build basic aerobic fitness, our endurance base. Most endurance athletes would benefit from spending a proportion of their time developing this base, regardless of event duration, or their fitness profile. Training in Zone 2 enables the athlete to ‘push up’ their lactate threshold from below. It is only when you have completely ‘pushed up’ the lactate threshold can you then switch over into Zone 3 to begin ‘pulling it up’ (as described in Pushing and Pulling). One of the biggest mistakes athletes (and coaches) make is to not fully exploit Zone 2: not doing so risks blunting the potential improvements in fitness, and also, exposes the athlete to breaking down with increased training loads later on in the periodised year.

A coach may suggest a longer period of time in Zone 2 when a rider’s strengths / weaknesses profile suggests its need. Elite cyclists can see their LT at 75% of VO2max, whilst the average club rider may struggle to pass 65%. Two athletes of the same VO2max expressing different lactate thresholds possess different endurance ability – the higher your lactate threshold, the harder you can exercise without producing lactic acid, and the longer you can withstand fatigue. The other scenario that may move a rider toward more Zone 2 training is when the chosen event speciality is between 3 to 5 hours: so longer road racing events, and longer distance time trialling (i.e. 100 miles).

A common use of Zone 2 training is when high volume / low stress training is needed. This can be when an athlete needs to lose fat mass, or when a break from higher intensity training is needed, without a compromise in endurance. The body is able to recover very quickly from Zone 2 rides – making it an ideal zone to use alongside other event preparation e.g. when an endurance event track rider is doing two sessions a day.

What part of the periodised year would I train in Zone 2?

The obvious place in the periodised year to use Zone 2 is in the transition time following the end of season break. Base miles may begin in November, and carry on into December – the Zone 2 work allowing aerobic fitness to be developed before the more serious Zone 3 / endurance capacity training enters the programme. Typically, an athlete would benefit from 10 to 12 weeks of training in Zone 2. The latter part of this block would begin to see integration of Zone 3 blocks. In practise, there are no hard and fast rules for periodisation and it is likely that zone 2 training will play a big part in any endurance athletes program throughout the year. At the 2010 PBscience Winter workshop, Dan talked through some of key considerations in planning your training in a presentation entitled Approaches to Periodisation.

What are the benefits to training in Zone 2?

In a recent study of endurance runners1, it was found that the training programme incorporating a greater proportion of Zone 2 type work lead to greater overall training gains in the 5 month period studied. And this is not uncommon. Indeed, a recent study in Sport Science laboratories at Brighton observed a 15% improvement in lactate threshold in just 6 weeks of Zone 2 type training! Even though most athletes have a higher initial fitness than those generally recruited to research studies, we could assume an improvement in physiological function will follow training of this type.

In one study of elite professional cyclists2, pre-competition training (which consisted of ~75% of sub-threshold training) brought about marked changes in the biochemical processes during exercise. Summarising the research literature of the past 30 years (some of which has used analysis of muscle tissue) endurance training (of the intensity equating to Zone 2) brings about the following physiological adaptations:

  • Increased plasma volume
  • Increased mitochondrial enzymes within the muscles
  • Increased capillarisation of the muscles
  • Increased muscle glycogen storage
  • Increased use of fat for energy production
  • Inter-conversion of fibre type towards slow twitch biochemical profile

All of the above bring about a reduced blood lactate accumulation for a given workload: predominantly by reducing lactic acid production in the muscle, but also possibly by increasing clearance of lactate from the system too.

Zone 2 may also prove to be a useful intensity to help freshen up an athlete’s psychological state. We may also see pedalling skills improved, and therefore improved efficiency. More on this in another PBscience factsheet! Essentially, we can see that adaptations from Zone 2 exercise help get the body best prepared for exercising regularly – optimising the engine. What we won’t see are improvements in other aspects of the system – so don’t expect to see your VO2max change very much after Zone 2 training blocks!

What can we expect from Zone 2 training?

In a standard base endurance ride, an athlete training in Zone 2 is likely to experience the following:

  • Requires a little concentration to maintain in the upper part of the zone
  • Breathing more regular than at low effort (zone 1) but conversation can be continued whilst riding.
  • A low sensation of leg effort whilst exercising, but awareness of ‘having done something’ immediately post ride
  • Quick recovery, and can soon repeat the same effort (as long as nutrition is taken care of).


Key factors to remember when using this training zone

Zone 2 is not a taxing training intensity in itself: the main challenges to the athlete arise during repeated sessions, and the accumulating effects. After all, if the training didn’t impact on you somehow, it would not be a training session! Keep in mind:Snow_riding

  • Nutritional aspects – training just under the lactate threshold is the intensity where fat oxidation rates are at their highest (at ~40g per hour). However, there is also a high reliance on muscle glycogen utilisation (upto 70g per hour). With the longer rides in this zone being 4 hours or so, by this point, the athlete will be challenging their carbohydrate stores. Indeed, exercise intensity (and therefore quality of training) will be compromised if the athlete neglects carbohydrate ingestion prior to- and during exercise. Look to take in about 60g of carbohydrate per hour.
  • Time between sessions – as the muscular stress is low (and little muscle damage is induced) the major consideration is regaining the energy you have expended (if energy balance is required). Ensure you focus on post session nutrition to optimise glycogen resynthesis. You should be ready to train again within 12 hours, and almost completely recovered within 24 hours.
  • Impact on other training – Zone 2 training should not compromise other training if you have built up to the set volume in a steady and progressive manner. Four hours is not overly challenging if you have adapted to 2 hour and 3 hour rides first. It is not uncommon for athletes to also be attending to weight training / general conditioning at the same time in the periodised year. In most cases, it is advisable to perform the conditioning work prior to your ‘on the bike’ session: in order to make sure you are not compromising conditioning work training with glycogen depleted muscles.

Typical sessions

Training in Zone 2 would involve sessions of typically 2 to 4 hours. Your training week may involve frequent 2 hour rides, but 4 hour rides may be used more sparingly (maximum 2 per week for the average club athlete). The coach may use this endurance base training to also work on other aspects of the athlete’s profile.

Session 1: Steady endurance ride, 2.5 hours

  • Ø 15 minute warm up progressing through Zone 1 to Zone 2
  • Ø 2 hours of working consistently at the top end of Zone 2, maintaining a constant effort up and down hills (variable speed)
  • Ø 15 minute cool down, returning to Zone 1.

Session 2: Steady endurance ride with blocks of cadence work, 3 hours

  • Ø 15 minute warm up progressing through Zone 1 to Zone 2
  • Ø 2 hours of working consistently at the top end of Zone 2, including 4 x 10 minute blocks at a cadence >100rpm. Have at least 15 minutes of normal pedalling between blocks.
  • Ø 15 minute cool down, returning to Zone 1.

You will often see Zone 2 blocks within other sessions throughout the year, therefore, it’s a good intensity to become familiar with!


1.   Esteve-Lanao et al. J Strength Cond Res 2007, 21, 943-949.

2.   Lucia et al. Jpn J Physiol 2000, 50, 381-388.

Published in Free Factsheets