muscle recovery time?

It's different for everyone depending on genetics and protein consumption. Personally I could probably work the same muscles every other day, but I don't because they wouldn't be fully healed and I wouldn't have time to work my whole body. I have three working days, each being different muscles, then a rest day. Every few weeks I like to take 3 days off just to fully rest all of my muscles and the nervous system,

If you're just doing some low volume isolations every other day should be good. I do compounds 1st legs and abs, next day back, biceps and forearms, and final day being chest, shoulders, and triceps.

48 hours is the absolute minimum for a healthy young person. When a supplement such as protein or creatine advertise "reduces recovery time", they are playing with words in that if a person did not consume the right essential nutrients, it would prolong recovery time. But if you are already eating balanced nutritious meals, taking supplements is not going to reduce the recovery time to under 48 hours.

However, you may make more gains in that more nutrients as oppose to just enough will help grow more muscles. Just keep in mind that the realistic rate of muscle gain is only about 5 lbs per year. But that 5 lbs translate into a great deal of volume.