I am currently not using any supplements, so my recovery time is not as fast as it was going to be if I was using a supplement which aided with muscle fatigue and recovery. I had planned to workout everyday, with a 5 day, 1 body part per day split but I figure that workout plan is more suited for people on supplements, who recover fast enough to put their all into their workout day after day.
I was finding that not having a rest day left me feeling weak and still in pain from the continuous cycle of workouts. And the fact that i have been having a very hard time sleeping lately has not helped at all, in fact its a contributing factor to why I have been feeling weak.
I have decided I will go back to training 5 days a week still but this time I will rest for two days. As for the ab workouts I still feel a minimum of about 2 ab sessions per week is perfect for me right now but if I feel I did not exert myself or I did not feel challenged I add another hectic day of ab training. Some weeks I have such an intense workout that I still feel the burn 4-5days after my workout, and other times I feel I worked them really hard and I feel nothing. For me its about more than breaking a sweat I also enjoy the gym pain, its the best kind of pain ever, a symbol of hard work.
Having a enough sleep and proper rest is one of the most essential factor in muscle recovery.