Epoc and Training Intensity

In order to get the most out of your training it is important to have a well planned training programme that is periodised and allows you to monitor your improvement regularly. It is also important to monitor your body both during training and during recovery to make sure that you are getting the most out of it, you are not training when ill and you are fully recovered ready to race.

During training it is important that you monitor the intensity that your body is working, not just the splits that you are getting on the indoor rower. This is normally done by monitoring your heart rate during exercise and recovery to make sure that you are exercising in the correct training zone and that you are fully recovered between sessions. Until recently this was the best monitoring method available outside of the laboratory. It is now possible using the Suunto T6 wristop computer to increase your level of monitoring by adding to heart rate six other areas:

Excess post-exercise oxygen consumption
Training effect
Oxygen consumption
Energy consumption
Respiratory rate
The most important of these is the excess post-exercise oxygen consumption (EPOC). EPOC is 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.
EPOC is given as a numerical value that is calculated from the duration and intensity of the exercise and other physical and mental factors affecting your bodyincluding stress and fatigue.
The greater the intensity and the longer the duration of a training session, the higher the EPOC value measured from the session.
EPOC accumulates faster when training intensity increases than when the duration increases. This means that low-intensity 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, the physiological training load on your body and EPOC may be higher. Many factors affect EPOC during training including 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 accumulated during training may begin to decrease during the session, if the training includes sufficiently long rest periods, lower intensity periods or sufficient cool down built into the session. Although EPOC decreases fastest during complete rest, light cool down exercise after hard training will help the total recovery. Cool down increases the circulation, flushing the lactic acid from the muscles faster and speeding up recovery.
All substantial physical activity after the actual training session continues to consume energy delaying the start of full recovery.
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, cycling and rowing.

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 rowing, 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.
Recording a training session on your Suunto t6 then downloading it into the Suunto Training Manager software will allow you to produce the following information from your own data.

  • Does heart rate influence EPOC?

Yes. The higher the heart rate in relation to the maximum heart rate, the higher the EPOC.

  • Can I speed up the decrease of EPOC?

Yes. Complete rest is the fastest way to decrease EPOC. However, after high -intensity training, you should do some light cool down exercises even if this slightly delays the start of full recovery.

  • Why does EPOC only increase at the start of training, after which it stays nearly the same or even decreases?

In low-intensity training EPOC will not increase noticeably after a certain time. In low-intensity but long-duration training, EPOC will be lower than in high-intensity training. However, continuing training even after reaching the EPOC peak value is worthwhile, because long duration, low-intensity training will develop your base fitness and your body's ability to cope with hard training.

  • I always run the same distance in the same time. Why is my EPOC value sometimes higher, sometimes lower?

Even if training sessions are identical (same distance, same time), it may be harder on your body on one day, and easier on another. On a good day, the same training will have a lower impact on your body than on a bad day. Factors increasing EPOC include dehydration, stress, sleep deprivation, or the start of illness.

  • Why is my EPOC sometimes lower after training while tired than after an earlier, completely identical training, I did while well rested?

In certain situations, your body reacts to training by lowering the heart rate and maximum heart rate even if your body is clearly not fully recovered. This may result in a lower-than-usual EPOC. We recommend paying attention to such abnormal behaviour of the EPOC values and ensure that your training program includes a sufficient amount of rest, since continuous training without sufficient recovery leads to overtraining.

  • Is training more effective the higher the EPOC?

EPOC is an indicator of how hard the exercise session was to your body and how much your physiological homeostasis was disturbed, but the quality of training always depends on your personal goals and situation. It is important to have variety in your training program. In order to develop, you need both high-intensity training where EPOC rises to high levels, and long-duration, low-intensity training and recovery exercise where EPOC remains low.

  • I did short duration, high-intensity training, after which I was exhausted. Why was my EPOC value low?

In short-duration, maximal or near-maximal exercise, the cause of exhaustion is usually an extreme rise in acidity (lactic acid level) in your body, which makes you unable to continue training. Longer, more sustainable workouts may leave you feeling less exhausted but will cause more total stress, thus resulting in a higher EPOC value.

Each training session you do has some kind of effect on your body. EPOC makes it possible to objectively measure whether the effect of the session was sufficient to improve your fitness level. This is called the Training Effect and can be determined by comparing the EPOC value measured from the training with the athlete's performance level.

Learn about the Training Effect

Learn about the Suunto t6c


Receive Our Monthly Newsletter
JDS Sportcoaching, LLC respects your privacy. We will not sell or share your contact information without your expressed consent.