Why use lactate testing?

Swimming Technique, Oct-Dec 1998 by Rushton, Clice

Lactate testing is the only practical way to find certain essential information about your swimmers.

This is the second in a series of articles on lactate analysis:

Lactate testing shows you the changing relationship between effort and speed. More effort means more lactate. At low intensities, speed increases faster than the lactate; at higher intensities, the lactate changes faster than speed.

It's the same as working a little harder for a big reward, then having to work much, much harder for further, smaller and smaller rewards. The rewards, i.e., swimming faster, are incremental.

Coaches have always tested their swimmers in a variety of ways, but lactate testing will give you information which can be more valuable. This article explains the testing procedures which, if used systematically, will provide that information.

The Race Model

A lactate race model can be described as follows:

Start and early meters: Decelerate from the dive to race pace and hold with as little lactic acid production as possible.

Mid-race part 1: Swim as fast as possible, using aerobic metabolism.

Mid-race part 2: Continue swimming fast, even accelerate, producing increased levels of lactic acid.

End-part: Accelerate-or decelerate as little as possible-under stress and fatigue, tolerating the extended time the muscles have to operate under highly acidic conditions.

Each of these portions of a race is addressed in a systematic training regime. Each of them can be tested to ascertain the current status, and a training program can be designed based on the results. The subsequent training effect can be gauged by re-testing.

Lactate information shows you the oxygen use where it counts-in the muscles at the cellular level. Heart rate monitoring shows you the oxygen demand by the muscles; it does not show the oxygen use. Oxygen use-not oxygen demand-is a limiting factor in swimming fast.

Three Vital Components

With proper test procedures and simple computer analysis, information can be gained which encapsulates all the components of successful performance in swimming. For all Olympic swimming events, the physiological components which ensure success are:

Endurance-the velocity during, predominantly, aerobic work (E). The lactic acid value at maximum effort (M).

The power relationship between these first two components (P).

Aerobic Work

Aerobic work means endurance or stamina swims. If the aerobic component is measured at a level of intensity suitably reflecting the aerobic requirements of the swimmer's event, then an accurate indication of the endurance capacity can be shown.

Many programs have used 4mM of lactate (4 milliliters of lactate at maximum effort) as their standardized measure of aerobic intensity. If you choose a very low, or very high intensity, your results will not reflect the endurance capabilities accurately, so 4mM is a good choice and enables you to compare your results with those of many other programs.

Scientists tend to measure the velocity, or speed, at 4mM, but coaches are comfortable talking about times rather than velocities, so the time at lactate 4mM is more meaningful. This is abbreviated to tV4. Different levels would be tV2 or tV3, etc.

Measures of Endurance

Measuring endurance capabilities in swimmers is one of the easiest coaching tasks. Any timed-distance swim will provide information about the endurance capabilities of the swimmer. You will know how fast he is, but even if he gives a maximum effort, you will not know how much energy he has used to produce the speed. If he does not give maximum effort, you will know very little. Lactate testing during one of these sets will tell you the effort precisely, even if he swims sub-maximally.

Maximum Lactate Value

Lactic acid moving out of the muscles becomes lactate when it enters the bloodstream. As swimmers apply more effort to swim faster, we can measure more lactate. If they train to produce very high amounts of lactate and control their application of power, they will be able to swim even faster.

The highest lactate result of a test is, therefore, a very important parameter-it corresponds to the maximum speed. Its abbreviation is LaMax.

The Relationship between tV4 and LaMax

This relationship describes the swimmer's ability to increase speed through the application of power and to apply power throughout the range of intensity. It is not possible to measure this swimming-specific power on land.

The relationship is dependent on factors internal to the swimmer. These include fiber-typing, muscle cross-sectional area and total fiber surface area. This component is the third vital component of sporting success and can make just as much difference to race performance as tV4 and much more difference than LaMax. By measuring these three vital components, we can see a virtual picture of the swimmer.

Metabolic Triumvirate

All three vital components are interrelated. For example, training which is designed to produce changes in aerobic conditioning will, necessarily, also change the LaMax and the relationship between aerobic conditioning and maximum lactate. The only way you can be aware of the degree of change or which way to structure your program to produce change is by lactate testing.