Lactate Physiology and Sports Training
Part 3 -Reasons for Lactate Testing
So, why measure lactate? Basically there are five very important reasons to measure lactate for an athlete.
Some coaches have suggested a sixth. These are:
- 1. Measuring lactate levels provides the best measure of the stress
exerted on the muscles during a workout.
- When a coach specifies the intensity or speed of a workout, the coach
should know the lactate that this intensity or speed will generate. Otherwise
they are guessing what the workout will accomplish.
- When an athlete produces lactate in a certain muscle group, it means
that some of those muscles can no longer process all the needed fuel
aerobically. The amount of lactate produced is an indication of how limited
the aerobic energy system is in the exercised muscles. Exceeding the current
limit of aerobic metabolism is what will cause the muscles to adapt and
eventually process more fuel aerobically. Up to a point, the more stress
placed on a muscle's metabolism, the more adaptation will take place. It will
never be possible to process all fuel aerobically, but most athletic events
depend on high levels of aerobic processing capacity. Eventually the athlete
will start to see lower lactate levels at every sub maximal effort as the
muscles process more energy aerobically.
- Because the amount of lactate generated at a specific effort shows the
limits of aerobic metabolism it is the best measure of the stress a specific
exercise program is generating. When a coach knows the lactate profile for
each athlete (they will all be different), the coach can specify individual
training programs. Athletes will all respond differently to the training
programs, too. Without lactate tests there is a lot of guessing. Good coaches
are excellent guessers but even they may not be sure about every athlete.
- Until recently, a laboratory was the only place you could measure
lactate. So coaches and athletes have relied on imprecise measures of
metabolic stress such as heart rates, perceived effort or distance tests.
However, with the introduction of a portable lactate device it is possible for
coaches to measure lactate anywhere, in the gym, at the pool, on the track, on
the road, on the water, at the rink, on the ski trails and slopes and even at
the top of a mountain.
- Other methods of measuring stress are either imprecise or very
impractical. When using heart rates to estimate the stress put on an
athlete's muscles, a coach is substituting this measurement for lactate
levels. But this is a hit-or-miss proposition. The stress in the muscles
associated with a particular heart rate or percent of maximum heart rate can
vary substantially from athlete to athlete. So without a link to lactate
levels, heart rates can be very imprecise.(See section on Lactate and Heart Rates.) Nearly every article or book
on the use of heart rate training discusses the importance of measuring
lactate but says that it is impractical for the typical athlete because of
cost or the unavailability of lactate testing equipment. However, given that
there is now a 4 oz lactate analyzer that is quick and easy to use, can be
taken just about anywhere and provides laboratory accuracy, it is difficult to
say that measuring lactate is impractical7. When calibrated by
occasional lactate testing, heart rates can be a very useful indicator of the
intensity of a workout. But for some situations heart rates and perceived
effort will always be very poor measures and are rarely a good surrogate for
lactate testing. Neither will tell the coach how well an athlete is clearing
lactate from his or her system. And above the lactate threshold heart rates
are very constant and are not an indicator of what is happening in the
- Another method often used to measure fitness or intensity of training
is oxygen consumption (VO2). While it is desirable to have very high aerobic
capacity, it is important to emphasize here that a large percentage of aerobic
training has little to do with increasing the ability of the athlete to
provide more oxygen to the muscles. Very often there is plenty of oxygen
available to the athlete's muscle cells. Factors other than lack of oxygen
limit the aerobic process. One of the most important limitations of aerobic
metabolism is the lack of sufficient enzymes to facilitate the aerobic
process. Another important factor is that the parts of muscle cells called
mitochondria, which are necessary for the aerobic process, may not be dense
enough to produce all the energy that is required. Both enzymes and
mitochondria will increase with training of the specific muscles. Hence an
emphasis on improving the body's ability to process oxygen may provide only
limited performance benefits if the specific muscles used in competition are
not also being trained. While the ability to process large amounts of oxygen
is very important especially during competition, the muscles involved in the
exercise must be able to utilize the oxygen.
- 2. Measuring lactate is the best way to find the lactate
- We have pointed out that the lactate threshold is an important marker
for athletic training. Exercise at this effort level is thought to generate
the most stress possible during a workout. However, unless a coach knows the
LT of each athlete they are just guessing how best to train them. Several
surrogate tests have been developed because lactate testing was not readily
available until recently, but none is as accurate as actual lactate
measurement. Athletes may go through several different types of protocols to
estimate the threshold and then not be sure if the right effort has been
- One coach said that after a year of working with an athlete, he could
estimate the threshold to within a couple of beats using a heart rate monitor.
A exercise physiologist listening to the coach describe the series of tests
his athletes went through said:
Why don't you just measure it? It won't take a year or a week. It can be done in an hour and then verified in
a half hour during a scheduled workout. When it is over you will know a lot more than what the heart rate
will tell you by itself.
- 3. Measuring maximum lactate production is an excellent and
easy way to assess the anaerobic system.
- Speed requires that muscles produce energy as quickly as possible.
Thus, at high speeds, athletes produce large amounts of lactate very quickly.
The level of lactate in the blood is one of the best measures of how fast the
muscles are producing energy and how fast the athlete can go (the higher the
lactate the better). As an athlete gets nearer to a major competition, the
anaerobic system should be trained more intensely so that the athlete is ready
for the important race.
- While many athletes spend a lot of their training trying to limit
production of lactate and shuttle it quickly from one muscle to another, they
also train to produce as much lactate as possible at race time. So for peak
performance athletes train their bodies to simultaneously produce large
amounts of lactate in one energy system and limit it in another. We call this
the Lactate Training Paradox.
- There are two caveats that go with training the anaerobic system and
its measurement. The first is that too much training to produce high lactates
could negatively affect the training of other energy systems, especially the
aerobic system. The second thing a coach should be aware of is that it is not
possible to compare one athlete to another using this measurement. Because one
athlete has higher levels of blood lactate than another after a maximal effort
does not mean that the athlete with the higher blood lactate readings will
produce a faster time or a greater anaerobic effort. But an athlete's highest
max lactate is often prduced by a personal best time.
- 4. Measuring lactate is necessary because too much lactate in
the muscles can cause muscle damage.
- We have just pointed out that generating lactate is essential for
adaptation. Also we have discussed why generating high lactate levels in a
competition is essential for a good performance. However, producing too much
lactate too often can be harmful. Frequent production of high lactate can
cause muscle damage and impair performance, sometimes for extended periods of
time. Thus a coach should be aware of how often the athlete is entering the
danger zones of high lactate and acid production. As mentioned above, heart
rates and perceived effort are poor indicators of this type of stress.
- Every athlete has felt the pain and the inability to use muscles
normally at high levels of intensity. Current thinking of sports scientists
indicates that it is not the lactate itself that produces the pain. They
believe that it is the acidic condition produced by hydrogen ions when the
lactate is created that is the cause of the problem. However, by controlling
the lactate in the muscles an athlete can control this acidic condition. About
85% of the hydrogen ions produced in the muscle during exercise are produced
with the lactate and most are cleared with the lactate. This leads us to the
fifth reason for measuring lactate.
- 5. Measuring lactate allows a coach to assess how well an athlete is clearing lactate from the fast
twitch muscles and using it elsewhere.
- We will discuss this important aspect of training several times. It
seems that the ability to clear lactate from the muscles where it is produced
is one of the important effects of training for nearly every athlete. In
competition, if athletes are able to clear lactate quickly, then they will be
able to utilize the fast twitch muscles for a longer time before high acid
levels shut them down. During workouts, if athletes can clear lactate from the
muscles quickly, they will be able to repeat high intensity sets or routines
more often. Coaches should be aware of how long it takes an athlete to clear
lactate and what level of recovery effort speeds this clearance.
- If a coach observes an unfavorable change in clearance patterns, it may
indicate either a potential problem with the athlete or the training. In
either case the coach will know that something has to be done to reverse the
- 6. Measuring lactate encourages the athlete's interest in his
or her own training program.
- Several coaches have told us that after they started measuring lactate,
many of their athletes became much more interested in doing their workouts.
They were very interested in what the test results might be telling the coach.
The coaches said that both they and their athletes started to understand more
clearly the factors affecting the athlete's performance.
- One last question: Who should use lactate testing?
- This question provokes a lot of strong reactions. We are selling
lactate analyzers so we are suspect. However, we will give you our answer
anyway. We believe that any athlete who is physically and emotionally mature
and is serious about training can benefit from lactate testing. Notice we did
not mention anything about elite. We have witnessed several athletes who are
very serious about their sport and want to do the best they can. They would be
thrilled to be a contributor on a Division III collegiate athletic team or
qualify for the Ironman championship. They are far from elite but are just as
serious about their sport as those going to Olympic trials. They will benefit
just as much from lactate testing as the Olympic finalist. They may finish 3
hours behind the winner at the Ironman but they are ecstatic about their
performance. If someone is going to put in the long and arduous hours to
train for an event, they should make the most of those hours.
Lactate tests require that the coach be very conscientious in
conducting the test. Thus, lactate testing should only be done in carefully
controlled situations. This doesn't mean that the cyclist cannot take a
lactate test while on the road. It just means that every test should follow
proper handling procedures for accuracy as well as sanitary reasons.