Look up Body For Life, if you are interested in adding muscle.
It's a D&E routine based on basic body building principles and routines.

If mass isn't what you want, look up bodyweight exercises.....things like pull ups and pushups. You won't add much mass with these kinds of exercises, but general fitness is a good idea. Even professional cyclists do strength training during the off season (if you can call benching 125lbs strength training).