Sweetspot plus

sweetspot-plusAim of Session

An advanced test of your endurance. 


Session description

WARM UP: Ensure 15 mins warm up before starting the efforts, worth considering having this contain 5 mins in low end zone 3 to make sure the engine is ready, include this time within the session duration

MAIN SET: Perform 2 x 20 mins blocks of effort in the upper end of zone 3 i.e. approx 90% of your 25 mile power (or FTP). THIS IS NOT A ZONE 4 EFFORT, but more controlled. 10 mins of easy pedalling in between. Have 10 mins zone 2 before upping the effort to finish the ride with a sustained tempo block in zone 3 (usually ~30 mins).

COOL DOWN: add 10 mins of spinning onto session duration if required, not included in session duration


The first part of this session is identical to the standard sweetspot session. The addition of ~30 minutes in mid zone 3 is an additional test of your endurance. The two sweetspot blocks will likely leave you with a level of fatigue in a cross section of your muscle fibres - specifically, the work in high end zone 3 will significantly dent your muscle glycogen stores. This will translate to the final zone 3 block having to be performed using a larger number of fibres from your fast twitch pool - quite different to a standard zone 3 workout.

Application for the Rider

This level of endurance is important for athletes looking to compete in long distance time trials, road racing and some of the tougher sportives. This session should only be used after showing the ability to complete entire rides in zone 3 and comfortably complete the standard sweetspot session. Glycogen utilisation is high during this workout so it is a real test of the level of your stored muscle glycogen and ability to consume exogenous carbohydrate during the workout.

Practicalities and tips!

  • We cannot stress enough - carbohydrate intake is key! Unless glycogen depletion is minimised the final 30 minutes in zone 3 will be very challenging or impossible.
  • Hydration is equally important. Your body will liberate the water that is required to store muscle glycogen if you start to get dehydrated - this will increase the rate of glycogen utilisation and bring forward the point of fatigue.
  • When new to this session you may wish to guide the zone 3 effort by heart rate and only observe the power this equates to in your subsequent analysis.
  • As you become fitter and for more advanced athletes you may wish to ride at zone 3 power and see the effect this has on your heart rate.

Evaluation of the session

  • First check your sweetspot blocks as described for the standard session - check power, heart rate and duration.
  • Now check the relationship between heart rate and power in the final 30 minute block. Did zone 3 power correspond with a zone 3 heart rate or vice versa?
  • A higher heart rate then expected is a sign that you are having to recruit the less efficient fast twitch fibres to meet the required output. This is good - the aim of this session is to improve the endurance capabilities of these fibres - but beware of excessive 'decoupling'. Be careful not to become over-fatigued and require extended recovery. See the factsheet entitled The relationship between heart rate and power for a more detailed explanation.