Lactate threshold test

Lactate-threshold-testAim of Session

To determine/monitor you Lactate Threshold


Session description

This lab test involves a number of stages, with exercise intensity increasing by 10-25W every 3-minutes. At the end of the 3-minutes, a fingertip blood sample is taken for the analysis of blood lactate.


The lactate threshold is a term that is often referred to in a number of sports that involve efforts over a long distance. For steady-state exercise, the body provides energy by breaking down fat, blood glucose or glycogen stored in the muscle.  As a by-product of energy production, a substance known as pyruvate is formed. When exercise intensity is fairly low, the aerobic energy system is dominant. The large supply of oxygen to the muscles allows the pyruvate to be ‘oxidised’ (i.e. cleared). However, at a higher intensity there is not enough oxygen available to oxidise the pyruvate, meaning energy has to be supplied anaerobically. This results in the pyruvate being converted to lactic acid. When the lactic acid exits the muscle and hits the blood, it becomes lactate and hydrogen ions. An increase in the formation of lactate is an indirect marker that a rider is beginning to fatigue.

The lactate threshold represents the highest exercise intensity at which lactate does not accumulate in the blood. This is generally occurs at about 60% max intensity (at the top end of zone 2). When the exercise intensity increases at the beginning of each new stage, the production of lactate will change. This change in lactate production occurs because the contribution of aerobic and anaerobic energy systems has changed. Using 3-minute stages allows the lactate response to stabilise for each stage and give a true reflection of your physiological state. By plotting exercise intensity against blood lactate, we can draw a profile of your lactate response and identify the lactate threshold. See the factsheet on demystifying the lactate threshold for more information.

Application for the Rider

The lactate threshold is considered as the upper limit of zone 2, where some long-duration steady-pace mileage can be put in during the winter months and early season. Training close to this intensity will gradually increase this threshold, laying down the foundations for endurance performance. Using zone 2 training is vital. You can read about where it fits in to the whole plan in the factsheet on zone 2 training.

Practicalities and tips!

Lab testing can be a daunting prospect - for the first time athlete, but also sometimes more so for the second time around (as you have 'scores' you want to beat!). Prepare for the testing visit like you would a race - rest the day before, fuel well and be sure to get a good night's sleep. All these factors help the scientist control the testing conditions, making your results more valid to feed into your training. For more information on the lactate threshold testing, watch the video in our resources section.

Evaluation of the session

Your coach will provide you with a full lab test report - in that document you will also be able to compare your results with normative data (from other cyclists) as well as your progression if you have performed this test previously.