Lactate Threshold Training
Lactate threshold training will help to improve performance times in endurance events such as distance running, cycling and swimming. As its name suggests, this form of conditioning is designed to increase the exercise intensity at which the anaerobic or lactate threshold occurs.
There is some confusion amongst coaches and athletes as to the role of blood lactate and lactic acid in the body. Central to this confusion is how it contributes to fatigue. But regardless of the underlying causes, the accumulation of blood lactate remains a good indicator for subsequent exhaustion (1) and can predict performance in many endurance events (2).
During submaximal exercise, lactate concentration in the plasma remains at a near resting level. As the intensity increases, there comes a point when blood lactate begins to accumulate rapidly in the blood (1). Some researchers contest this suggesting that no specific breakpoint or threshold exists and that lactate accumulation is continuous (3,4,5).
However, from a practical point of view what is most important is that lactate threshold training can delay blood lactate accumulation, in effect shifting the lactate curve to the right. See the graph below:
Although it is difficult to accurately measure lactate threshold outside of a laboratory setting, there are some field tests that may be worth considering in order to determine your own anaerobic threshold. You may even want to consider using a portable lactate monitor and testing kit, which have become much less expensive in recent years.
There is a substantial body of research that shows training at or close to the lactate threshold increases the intensity at which it occurs (6,7,8,9,10,11,12,13). Recall that lactate threshold is often expressed as a percentage of VO2 max. For example, if an athlete reaches VO2 max at a running speed of 24km/h (15mph) and lactate begins to accumulate at 16 km/h (10mph), they are said to have a lactate threshold of 67%.
World-class endurance athletes typically have thresholds of up to 90% VO2 max compared to 50% in untrained individuals (1).
Lactate Threshold Training Sessions
Threshold training (also known as pace, tempo or aerobic/anaerobic training) can be either continuous or intermittent in nature. Both require an exercise intensity at or slightly above the lactate threshold.
One of the most common ways to gauge lactate threshold training intensity is to monitor heart rate. While, a very quick and simple method is to simply assume your lactate threshold will occur at 85-90% of your maximum heart rate, this method lacks accuracy and reliability for many athletes. If you do want to determine training intensity this way, use the Karvonen formula rather than simply deducting your age from 220.
A more reliable method is to determine your heart rate at the lactate threshold and then to train at this heart rate intensity. This is by no means flawless however, especially as heart rate often tends to rise slowly over prolonged exercise periods without increases in intensity a phenomenon known as cardiac drift.
Cyclists can use a power meter to determine the work rate at lactate threshold and thus a suitable intensity for lactate threshold training sessions.
Here is a typical interval lactate threshold training session:
|Interval Training Session|
* LT = Training intensity at Lactate Threshold measured via heart rate or power output etc.
And here is a sample continuous lactate threshold training session:
|Continuous Training Session|
1) Wilmore JH and Costill DL. (2005) Physiology of Sport and Exercise: 3rd Edition. Champaign, IL: Human Kinetics
2) Farrell PA, Wilmore JH, Coyle EF, Billing JE, Costill DL. Plasma lactate accumulation and distance running performance. Med Sci Sports. 1979 Winter;11(4):338-44
3) Hughson RL, Weisiger KH, Swanson GD. Blood lactate concentration increases as a continuous function in progressive exercise. J Appl Physiol. 1987 May;62(5):1975-81
4) Campbell ME, Hughson RL, Green HJ. Continuous increase in blood lactate concentration during different ramp exercise protocols. J Appl Physiol. 1989 Mar;66(3):1104-7
5) Dennis SC, Noakes TD, Bosch AN. Ventilation and blood lactate increase exponentially during incremental exercise. J Sports Sci. 1993 Oct;11(5):371-5; discussion 377-8
6) Ready AE, Quinney HA. Alterations in anaerobic threshold as the result of endurance training and detraining. Med Sci Sports Exerc. 1982;14(4):292-6
7) Yoshida T, Suda Y, Takeuchi N. Endurance training regimen based upon arterial blood lactate: effects on anaerobic threshold. Eur J Appl Physiol Occup Physiol. 1982;49(2):223-30
8) Davis JA, Frank MH, Whipp BJ, Wasserman K. Anaerobic threshold alterations caused by endurance training in middle-aged men. J Appl Physiol. 1979 Jun;46(6):1039-46
9) Belman, MJ, Gaesser, GA Exercise training below and above the lactate threshold in the elderly. Med Sci Sports Exerc. 1991;23,562-568
10) Evertsen F, Medbo JI, Bonen A. Effect of training intensity on muscle lactate transporters and lactate threshold of cross-country skiers. Acta Physiol Scand. 2001 Oct;173(2):195-205
11) Weltman A, Seip RL, Snead D, Weltman JY, Haskvitz EM, Evans WS, Veldhuis JD, Rogol AD. Exercise training at and above the lactate threshold in previously untrained women. Int J Sports Med. 1992 Apr;13(3):257-63
12) Acevedo EO, Goldfarb AH. Increased training intensity effects on plasma lactate, ventilatory threshold, and endurance. Med Sci Sports Exerc. 1989 Oct;21(5):563-8
13) Henritze J, Weltman A, Schurrer RL, Barlow K. Effects of training at and above the lactate threshold on the lactate threshold and maximal oxygen uptake. Eur J Appl Physiol Occup Physiol. 1985;54(1):84-8
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