We all know that we can go to the gym and kill ourselves. But it's what we do away from the gym that makes things happen. We have to have a rest day or 2. I make my rest day on Sunday, because it's the easiest day to pick and it makes for a great break most of the time.
Just because it is your off day, doesn't mean you have to not do anything. Go hiking or something, maybe take a couple of walks during the day, anything to stay active, but not overly active. You need to realize that protien is a big thing in rebuilding muscle. So if you can add protien shakes or protien rich foods to your diet.
Certain fruits are great for helping in recovery, cherries are proven to cut muscle recovery time in half. Adding berries will do the same. So keep these things in mind