As we iterated before on other pages of this site, many aspects of bodybuilding are away from the gym, but, despite this fact, they have an impact just as important on the overall result, as the training itself has.
Two such factors - closely linked to one another - are overtraining and recuperation.
As it’s well known, actual muscle growth does not occur in the gym - despite the feeling of pump one experiences after a properly performed exercise. Most of muscle growth happens during the rest periods, periods which the body utilizes to recover from the wear and tear of the previous training session. As we pointed out in the ‘ training to failure’ section, muscle functioning involves an array of complicated chemical processes. In this process muscle fuel is used up ( glycogen) which gets oxidized and thus transformed into lactic acid. Lactic acid is but a byproduct of muscle activity, a kind of waste material the body needs to get rid of. Some of the cleansing operation takes place immediately as the set is finished - during the rest period between two sets - thus the muscle regains some of its capacity to contract again. ( around 70 -75 percent in a minute) However, for a muscle to completely recuperate from the stress of a full workout, the 3 minute max that it needs to pull itself together as much as possible on the spot, is not enough. ( you won’t replenish your muscles further, after 3 minutes of inter-set rest they’ll be about as rested as they would with any further pause) The remains of lactic acid need to be carried away though, and this is a lengthier process just as well as the replenishment of fuel to the muscle is.
Generally it is recommended that one give his/her body a period of about 48 hours between two thorough training sessions. Working a muscle every second day will most likely give it enough time to fully regenerate.
Some muscles of course regenerate faster than others. The bicep is the fastest in terms of recovery, the muscles of the lower back are considered to be the slowest.
As stated above, rest and overtraining are closely linked, the lack of the first creating the premises for the second to kick in.
Overtraining occurs when one fails to give a muscle-group its needed recovery period, taking it into another tough workout while it still bears the scars of the previous training.
This leads to slowing of development, or in extreme cases, it can halt it altogether. Plus it’s wasted time and resources until the bodybuilder figures out how to break out of the situation.
Remember the body is not a machine that can be used day and night and still perform undisturbed. Respect it and take good care of it. It won’t let you down.