Name: EPOC
Rating: 4 (3 reviews)
Author: prenard

EPOC stands for Excess Post-exercise Oxygen Consumption. It is an increase in oxygen uptake above resting levels that occurs during and after exercise.

Similar to how a car’s engine remains warm after being turned off, once a workout is over and you are back in your daily routine, your body’s metabolism can continue to burn more calories then when at complete rest. This physiological effect is called Excess Post-exercise Oxygen Consumption, or EPOC.

Also known as oxygen debt, EPOC is the amount of oxygen required to restore your body to its normal, resting level of metabolic function (called homeostasis).

Methods that are used in assessing training load may be broadly characterized as subjective and physiological measures. Subjective measures are easy to access, but do not always reflect physiological responses and recovery demand. Traditional physiological measures, such as oxygen consumption (VO2), heart rate and blood lactate, reflect mainly momentary intensity of exercise and not length of exercise or cumulative exercise load. There are also training load measures such as TRaining IMPulse (TRIMP) or Training Stress Score (TSS), but which does not have physiological basis or scale and therefore may be difficult to interpret.

EPOC is a physiological measure (amount of oxygen consumed in excess after exercise as measured in liters or ml/kg) that that reflects the recovery demand and the disturbance of body’s homeostasis brought by the exercise.
Measurement of EPOC has been possible only by analyzing respiratory gases with laboratory equipment thus being not applicable to everyday training.

The EPOC value is a measure of training load and cardiovascular fatigue. Its main purpose is to describe stress caused to the body during and after training activities.

Firstbeat Technologies (Finnish company), which provides to Garmin/Suntoo its analytics technology (VO2Max estimation, Recovery Time, Training Load, Training Effect, Performance Condition...), has developed a method using Heart Rate Variability (HRV) to estimate EPOC indirectly from heart rate measurement.

This was implemented in "old" Suunto watches T6C/T6D to display real time EPOC during training sessions. But it was never implemented in Garmin devices...

Firstbeat method is protected by patent and is not public. But there are some interesting available documents to understand major principles of its implementation.

This simple datafield uses these principles to compute a "speudo EPOC" value (which won't be exactly the same that the one generated by Firsbeat algorithms). It displays during an activity real time EPOC and its peak.

EPOC values is recorded in FIT file and can be displayed in Garmin Connect for post analysis.

This datafield needs some input parameters which can be entered using Garmin Connect:

* Your maximum heart rate (which can be optionnaly obtained from Garmin training zones)

Release History:

- V1.04 - 2019-02-06
* Update Edge 820 display
- V1.03 - 2019-02-06
* Update Edge 820 display
- V1.02 - 2019-02-06
* Update Edge 820 display
- V1.01 - 2019-02-05
* Add Edge 820 support
- V1.00 - 2019-01-29
* Original version