Endurance Sports and how you can use the lactate burn to improve performance!

In endurance sports lactate is a word that is thrown around a lot, but lactate isn’t your foe, in actual fact it can be your training buddy and help improve your training and performance!!

What is Lactate?

Lactate is a by-product of anaerobic metabolism (where oxygen demand is greater than the oxygen being supplied). The anaerobic system uses glucose (carbohydrate) as its fuel. A byproduct of glucose been broken down during anaerobic exercise (at high intensity) is the production of lactate and hydrogen ions. So basically when exercise intensity increases lactate formation also increases.  

Blood Lactate Accumulation

The terms commonly used to discuss lactate metabolism can often add to confusion related to understanding anaerobic metabolism and training. For the purpose of this discussion I will firstly describe two terms in order to aid in the understanding. The exercise intensity that an endurance athlete can continue at, for an extended period of time, without having to slow down is called the maximal lactate steady state (MLSS). Although lactate is still being produced at this exercise intensity the rate of this production is ‘stable’. As long as the athlete maintains this effort level the lactate level will remain constant. At small effort levels above this level will lead to a rise slowly in blood lactate and he or she will be forced to stop. This point where blood lactate accumulates is known as the onset of blood lactate accumulation (OBLA). But so what?


From an athlete’s point of view the MLSS is considered to be one of the best, if not the best, predictor of endurance performance. Generally the athlete who’s MLSS occurs at a higher intensity (or race pace) will be faster in an endurance event. In running the MLSS is often expressed as a particular speed (km/h) or in cycling it can be expressed as a particular power output (watts or watts/kg). Watts/kg is particularly useful to monitor a cyclist’s endurance performance whilst climbing. Therefore in order to assess improvements in training, analysis of the lactate response curve is critical. Effectively in endurance training we want to move the response curve up and to the right.

Measuring Lactate

The most common method for measuring lactate during exercise is using a graded test and to measure lactate at each level. The graph above depicts a typical lactate response to an incremental test on either a treadmill or cycle ergometer. If we were to examine this further we could measure heart rate and watt outputs at the same time and therefore theoretically assign heart rate and watt training zones for athletes. This is particularly useful in cycling. Studies have shown that even as little as 4 weeks speed endurance training, involving interval training at levels above the MLSS, have resulted in improvements in endurance performance (Iaia and Bangsbo, 2010). That’s just 4 weeks!!!

How to Apply Lactate testing to your training

So how would an athlete/coach apply the results of lactate testing to their training plan? Determining the point at which blood lactate starts to accumulate is merely the first step in the process. It is the ability to utilize this data for training that is really critical for athletes and coaches alike. Interval training sessions slightly above this ‘threshold’ value has been shown to positively influence endurance performance. For example an endurance runner performing intervals at a pace slightly above the pace at which MLSS occurs or an endurance cyclist performing intervals at a power output slightly above that at which MLSS occurs. This type of training theoretically could mean that the MLSS should occur at intensities higher than that recorded pre-training and thus there should be a positive effect on performance.

The bottom line for endurance athletes is that lactate testing is currently the best method to establish training intensity and ultimately to improve endurance performance. Lactate was once considered the ultimate foe to the endurance athlete. Current research strongly refutes this claim and actually points to it being a powerful biomarker for fatigue, an important precursor in the generation of new glucose and also an important factor in the generation of new mitochondria (power stations where energy is produced in skeletal muscle).

Train Smart and hard


Paul O’Donovan, Strength and Conditioning Coach DBSM provides a services in Athletic development, Team and group S&C Sessions, Sport Specific Training, Personal Training and Injury Rehabilitation

Check out Pauls bio and contact DBSM for information on coaching or lactate testing for athletes.