Basically, its like this.
When training, you place a stress on a muscle or group of muscles. Temporarily, afterwards, the muscle is slightly less capable, since it has been exhausted in several ways. In the very short term, stores of fuel have been depleted which require time to replenish (like minutes to hours). Also, a very slight amount of microscopic "damage" (and that term my be a bit strong but I use it just to illustrate a point) occurs, which requires healing. Also, the workload placed up the muscle in general causes a response in the body where it compensates by recuperating the muscle to be as strong/large as it was and a BIT larger/stronger.
Now, this healing process of the microscopic tears, and the response to INCREASE the muscles capacity takes MORE time. On the order of days.
How many days? That depends upon many factors (which have been stated in earlier posts). How hard you trained, the number of reps, sets, SPEED of execution of the movement, diet, rest, POST WORKOUT STIMULATION (like massage, icing, mild flexing, etc).
Those factors determine how long it takes to recover.
Now, overtraining happens when someone does not wait long enough for that recovery to occur before (over-) stressing the muscle again.
You could do a relatively light workout, and be ready for another in 3 days. You could go balls out, multiple sets to complete failure, strip sets, etc etc etc and require a good 10-14 days.
A trainer I worked with (who is NOT a flake trainer - this person DOES know their shit) made a very profound statement to me once ... "There is no such thing as overtraining, there is just under-recovery". While I don’t totally agree with that, it does illustrate an important point.
Overtraining is in part due to how hard you train, but it is equally a function of how long you wait to recover.
Most BB'ers train at a level which allows them to hit each major muscle group 1 time per week. That seems to be a good balance for most people.
Training so light that you can recover in like 3 days has the difficulty of you not REALLY stressing the muscle enough.
Training at the other extreme has problems. If you totally freegin wipe out a muscle group, so that it needs 14 days to recover, then this muscle group becomes the "weak point" when working other muscle groups, causing problems on getting a good whole-body routine to work. For example, if you TOTALLY blow out your shoulders on a killer balls-out workout .... that’s fine, maybe wait 14 days to do it again, but the problem is if you try to do chest in the meantime, you end up not being able to get a good chest workout, because your shoulders are needed for supporting functions while working the chest.
And before anyone comes on and says "no way you could do a workout which really requires 14 days to recover" I say BULLSHIT. It IS possible. As a test, I have done it on every major muscle group at different times.
So, the key to NOT overtraining is to hit that balance, that delicate balance, of resting enough for recovery, but not so long that atrophy starts (where you muscles, due to lack of stimulation, start to gradually weaken and get smaller).
Here is a very important point:
You can overtrain while on AS.
Read that again.
It IS possible.
I did it, and it was no picnic. Tired, but could not sleep, not hungry, felt like shit, etc.
I was doing (get this, for example ....) each body part 1 time per week. A typical workout for chest would be 6 different exercises, 3 sets each (not including warm-ups), each set to total failure, at about 8-12 reps for each set.
I was fine in the gym, I could do it. I would just focus, and keep going. But I was only allowing a week to recover, and even while on, it was not long enough.
So, it's important to know your body, how it responds, and how long YOU need to recover.
This is also a very good reason why it is best for people to train and gain as much as possible naturally before using AS. First, it its trains all of the supporting body functions (nervous system, lungs, heart, etc) which are taxed (a LOT) while on AS, but yet do not respond to the increases in capacity/strength/efficiency as much as muscles do while ON. Also, training for a long time naturally allows YOUI to get in tune with how your body feels, recovery time, etc, so that you are better able top "listen" and feel what is going on …. Better able to know when you can train again, and when its TOO early (I got a little over-anxious and did not listen to these signs while on, and overtrained).
Anyway, I hope this helps.
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