What is EPOC?
EPOC, Excess Post-Exercise Oxygen Consumption
EPOC is short for Excess Post-exercise
Oxygen Consumption and indicates the
amount of extra oxygen your body
needs for recovery after exercise. Due to
the physiological training load caused by
the exercise, your body consumes more
oxygen after exercise than during rest.
The more strenuous the exercise, the
higher this extra consumption of oxygen
(EPOC) is after exercise and the more
your body´s homeostasis is disturbed.
So, EPOC is an indicator of how strenuous
the exercise was. It is a numerical
value comprising the duration and intensity
of the exercise, as well as other physical
and mental factors affecting your
body, such as stress and fatigue.
So far EPOC has only been utilized in
exercise physiology research, because it
was only possible to measure it under
laboratory conditions. Suunto t6 is the
first device that allows the non-invasive
pre-prediction of EPOC already during
exercise, which in turn makes it possible
to monitor the exercise load and the
training effect.
HOW DOES EPOC ACCUMULATE?
The greater the intensity and the longer
the duration of a training session, the
higher is the EPOC value measured from
the session.
EPOC accumulates faster when the training’s
intensity increases than when the
duration increases. This means that lowintensity
training may not necessarily
result in a high EPOC value, even if the
duration of the training is exceptionally
long. With high-intensity training, however,
you can reach a high EPOC value
even in a short period of time.
In interval training, periods of high heart rate and periods of recovery follow each other. If the recovery periods are short, EPOC can reach a high value, as it will not have time to decrease during a short rest. The EPOC value attained from similar exercise can vary from day to day. On a good day, your body can handle the training more efficiently, resulting in a lower EPOC value, but on a bad day, physiological training load to your body and EPOC may be higher. Many factors affect EPOC during training, such as your hydration status and the temperature and humidity of the air. If you have performance anxiety or are nervous, this may increase the EPOC value.
EPOC IN DIFFERENT FORMS OF EXERCISE
EPOC is most useful for describing the
stress caused to your body by forms of
training that especially target the respiratory
and cardiovascular system. These
include endurance sports such as running
and cycling.
Training involving only small or limited
individual muscle groups (for example,
weight training) will not necessarily
result in an EPOC value as high as training
that taxes large muscle groups (for
example running or cross-country skiing).
Weight training may feel very
strenuous, because local muscle fatigue
and lactic acid hinder performance even
if your body still has energy for repetitions.
Fast-paced team sports often involve short but intense bursts of exertion intermingled with low-intensity exertion or rest. During the low-intensity periods, EPOC increases significantly slower than during high-intensity periods, and it may even decrease. For this reason, EPOC is usually lower in team sports compared to continuous exercise of the same duration. On the other hand, some team sports, like basketball, soccer and ice-hockey, allow for almost no breaks in the game and combine with a high level of intensity during play-time to allow EPOC to rise to very high levels.
