To make optimal recovery between workouts for growth the following must be in place:
1. Lots of nutrients at all times in blood to support muscle repair and growth.
2. Quality sleep / rest
3. Handle stress properly.
4. Healthy body including kidneys, heart, lungs, liver.
5. Optimal hormonal production.
6. Enough time between workouts to recuperate.
Considering items one through five are all in order, our goal is to properly adjust time between workouts to sustain an explosive growth spurt.
For an explosive growth spurt it is assumed that the more you train (as in experience not length of workouts) the more effective you will be at increasing your intensity. As you increase intensity more rest is required.
The workout program has three rest cycles. The first cycle has less recuperation time and more frequent workouts. As training progress is made, the training frequency is less. For example instead of training every second day like in the first cycle, the second cycle you now train every third day.
As you can see an extra day between training sessions is added as you become a more advanced trainee. As you are able to train more intensely you put more stress on your body. The extra rest time between workouts helps:
Keep Cortisone levels as low as possible to allow your natural anabolic hormones to have greatest growth effects.
Gives liver and kidneys time to recuperate to aid in explosive growth.
Decreases constant strain on tendons and ligaments from heavy lifting.
Gives muscles lots of time to repair and grow huge.