In this first article of three on lactate threshold training, I want to look at what this is to help you better understand the term.
In the second article, I want to look at how it relates to running economy, and how to determine your threshold.
In the third article of this series, I will consider how to improve your lactate threshold, and therefore how to race smarter – so stay tuned!
A definition of lactate threshold (LT) might read along the lines that it is an intensity during exercise whereby lactate (a by-product of the carbohydrate metabolism) starts to accumulate in the blood. In other words lactate is not being removed at the same rate as it is being produced hence the accumulation. When resting, or exercising at low intensity the amount of lactate in your blood stays low as at this intensity the rate of production equals the rate of removal. However go above that intensity and the rate of production exceeds the removal rate so lactate concentration rises. This then is lactate threshold, the exercise intensity above which removal no longer keeps up with production.
Lactate Threshold Pace
When we run we don’t all use similar amounts of oxygen at the same running speed. In terms of oxygen economy, like many things in running, some of us are more economical than others. When we consider the amount of oxygen consumed at the point of LT we call that LTVO2. Sports Scientists such as (Farrell et al 1979) have shown that as a performance predictor for distance runners that LTVO2 and the pace at which it occurs is more accurate than a measurement of VO2 max. This LT Pace is determined by only two factors: your oxygen consumption at LTVO2 and your running economy.
To illustrate this point and the advantage of high LTVO2 Farrell et al consider runners with VO2 max values that are identical say 56 ml of oxygen per kg bodyweight per minute (ml/kg/min) but different LT. Athlete A’s LTVO2 occurs at 44.8 ml/kg/min (80% of VO2 max) whilst Athlete B’s LTVO2 occurs at 39.2 ml/kg/min (70% of VO2 max). If the runners race at a speed that requires 42 ml/kg/min then Athlete A will be able to maintain the pace but Athlete B will have to slow down.