The lactate threshold (or anaerobic threshold) isn't so hard to understand, and is a very reliable indicator of endurance performance. Our performance is based largely on two factors, the percentage of our max that we are running at, and how efficiently we do so. Relate this concept to your own racing and it makes sense, if you were running a marathon distance at 100% of your max; it wouldn't be too long before you were carried home on a stretcher. Similarly, if you were running at 60% of your max but doing so in an inefficient manner, it would become very difficult to maintain that speed for the duration of the event.
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Now, to improve our performance we want to 1) improve our maximal capacity for exercise, 2) increase the percentage of max that we can compete at, and 3) improve the length of time that we can sustain this pace. The first involves some amount of your training being done at a high intensity, while all will be improved by increasing your lactate threshold, let me explain:
The graph below shows the levels of lactate for a given speed during following a lactate threshold test. There are actually two lactate thresholds, lactate threshold (LT) and the maximum lactate steady state (MLSS). LT is the point at which the levels start to rise above the baseline levels maintained at low intensity, and the velocity at LT (v-LT) is the speed at which this happens (i.e. our current level of performance). The MLSS refers to the maximal intensity that you maintain for approximately 30minutes with the levels of blood lactate continuing to rise exponentially. The MLSS usually coincides with the blood lactate level of 4mmol/L but can vary with individuals.
Now, the aim of training is to increase v-LT and v-MLSS, therefore pushing the curve to the right as seen in the graph below, where the old v-LT would be 14km/h and the new improved v-LT is 15km/h, likewise the old v-MLSS is ~16km/h and new v-MLSS is ~16.9km/h.
This is a pretty simple concept to grasp, if we improve our ability to tolerate lactate, while also reducing the amount that our bodies produce, we can train at a higher intensity before our exercise begins to decline with fatigue. This fatigue is largely due to ‘acidosis’, where an increase in lactate and more importantly hydrogen ions leads to a decrease in muscle function and blood pH, which introduces a whole host of detrimental effects. Knowing at what point your 'lactate threshold' occurs is very important in determining your training intensity and can dramatically improve the way you train.
Training Zones
Training intensity is generally divided into three zones based on the two lactate thresholds. LT is the upper limit for Zone 1and MLSS is the upper limit of Zone 2.
• Zone 1: Easy/recovery
• Zone 2: Transition
• Zone 3: Anaerobic (high intensity)
Most elite endurance athletes divide the time between these three zones in the ratio of 80:5:15. Very little time is spent in zone 2 because large volumes in this intensity are poorly tolerated and can lead to overtraining. However, for untrained individuals that may not tolerate high intensities and for trained athletes using it in small quantities, training in zone 2 around the lactate threshold does have benefits. If you are engaged in higher volumes of training a polarised model (80:5:15) is preferable, but if training volume or fitness or both are low, higher volumes of zone 2 may be better.
So, by establishing your lactate profile we can provide you not only with your lactate threshold but also with important information and precise heart rate zones at which training should take place and for how long. It's a no brainer, see you soon at Wheelworx.
Joe Warne
DCU Sports Science and Health
ChaseChaney Foundation
DCU Athletics Academy Sports Science / S & C
DCU Sport High Performance
Irish Runner Magazine
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