What time to train?

Edited by Dr. Davide Marciano

We often ask ourselves, "At what time do you need to train to get the most benefits?"

First we need to talk briefly about chronobiology which has shown that all human functions (production of hormones, changes in temperature, mood, etc.) have a rhythmic trend.
These rhythms take different names, but the ones that interest us most in sports are the CIRCADIAN OR DAILY ones which last on average 24 hours.
Let's analyze the circadian rhythms of the most important hormones that influence training:

GH exhibits three significant peaks during the day:

the two highest occur in the first and fourth hours after falling asleep.
The third, less influential, develops in the early morning.

Testosterone has two peaks:

one between 06.00 and 07.00.
The second around 17.30

Cortisol has its maximum peak between 07.00 and 08.00 in the morning.

So, to the question "What time do you need to train to get the most benefits?" we can answer:

If you want to lose weight, a morning aerobic session will exploit the GH peak and the maximum cortisol levels, as it is shown that the two aforementioned hormones have a lipolytic (slimming) effect.

Furthermore, studies have shown that if aerobic activity is done on an empty stomach, the GH peak will be even more powerful due to the hypoglycemia that will elevate it. In fact, it is assumed that the last meal was taken the previous evening, so the fasting at night will drastically reduce glycogen stores (the form in which man stores carbohydrates), so the energy lost during aerobic activity will be directly at the expense of fat.
If, on the other hand, you need to increase muscle volume, the training must be done in the early afternoon as you will be supported by the peak of testosterone (hormone responsible for muscle growth).
In addition, in the late afternoon, we can take advantage of the peak of adrenaline (hormone that increases energy and charge during training).
It is obvious that training at these times will give the maximum benefits, but if you can't respect them, don't worry. Better to train after hours than not doing it at all.

See also: Cronodieta

Chronobiology, hormones and circadian rhythms

Hormonal changes throughout the year