[quote]HOUSTON TEXAN wrote:
I just don’t understand the science behind recovery if I am not using the same muscle groups every day.[/quote]
You need a basic understanding of training principles.
Training provides a stimulus that causes your body to adapt. It does this by getting stronger and larger but it needs time for the adaptation to happen. If you hit it again the next day, the adaptation will not take place. The stimulus will be insufficient to cause enough stress to cause an adaptation.
Even if you don’t train the same body part back to back, you need to rest btween workouts. Each workout puts stress on the body that accumulates. You need at least 1 day off a week and few people should train more that 3 days in a row and then only if they are very careful with how they plan their workouts.
Muscle is built in recovery, not in the gym.
There is a ton of information on this site. Read some of it.