We are going to go a bit physiologically nerdy here (but don't worry, I will try to make this as simple as I can).

First you need to understand that hard tough training beats low intensity, relaxing training. Hard is of course relative, for my clients who are senior citizens, hard may be brisk walking. But for my national level athletes, hard could be repeated 200m sprints.

The main thing is that hard training is the best kind. We are already sedentary in most of our jobs and city lifestyles. Does it make sense if we do minimal work during our exercise time as well? That makes no sense.

EPOC is one of the coolest things about hard, intense training. It stands for "Excess-Post-exercise-Oxygen-Consumption".

When we train hard, we use energy faster than we can get it form oxygen in the air. This creates a "debt" in our energy system that will eventually need to be repaid. Sounds fair? Yup, all that energy came from somewhere! That somewhere is our anaerobic (no oxygen needed) sources that are already present in our cells.

So what have we just done? We have used energy beyond what we can sustain. If we were doing low intensity work, we could just breathe and get all the energy we need from our aerobic (oxygen needed) source. But no! We have exceeded that source and have tapped into other sources beyond what we can sustain.

It's payback time. Once the intense activity stops, the body starts to recover from that activity. During this time many things are happening to get the body back to a "normal" state. All these things use CALORIES! In fact the above-normal calorie usage can last 30 or more HOURS after the end of the hard training session.

Like I have always said, hard training is like putting money in a growth fund which makes money while you do nothing! With EPOC you literally burn calories in your sleep (just like many of the scam products out there claim) the only difference is that this is real!

Here is a short list and description of what your body is doing to get back to a rested, normal state. This is quite a long list of items and you will soon see why and how EPOC has the ability to help you burn lots of calories.

Restore ATP-PC: In simple terms, this means that we need to replenish the anaerobic sources in the body that we tapped into during the intense training

Restore Oxygen Stores: This gets our blood oxygen levels back to normal

Restore Heart and Breathing Rates to Normal: When a hard, intense exercise session stops, your heart rate, breathing and other functions do not suddenly go back to normal. This of course requires energy as well as time, because they are both needed to restore the body back to its regular functioning.

Restore Hormone Levels: There are several hormones (ok fellow nerds - epinephrine, norepinephrine, thyroxine, cortisol) that are increased. To clear the excess hormones out, the body has a chemical "pump" that needs energy to function.

Restore Body Temperature: During exercise, heat production is likely to excede heat removal. That means increased body temperature. For each degree celcius above normal, a 13-15% rise in calorie usage is needed for recovery.

Remove Lactate: Lactate is a by-product of exercise and it accumulates in muscles. It also takes energy to remove.

That's why all good fat loss programs make full use of the EPOC property. That means weight training with low rest periods, exercises that use the whole body and interval training as opposed to long slow endurance type activity which only burns calories during the exercise session.