There are benefits, both physically and mentally, to being active in other sports. There are also risks, especially considering what sport.
I wouldnt put too much thought into your dreams. The brain is very powerful, and likes to play when you are sleeping. If such things have been on your conscious, then they can very easily find their way into your dreams.
With that said, yes, save the leg for the champ.
As far as eating meat, chicken and light meat is fine in moderation, salmon is best. Id stay away from red meats, they are loaded with carcinogens, with that said we all eat red meat cause its so damn delicious.
(Specifically look at the health portion)