Stretch out your muscles before a job! Again this is really about the next day. If you don't stretch you'll probably be fine that day but the next day you'll potentially be in a lot of pain. Handyman work requires lots of bending and crouching and reaching for things over and over. For this reason it can provide a lot of varied exercise for you if your smart about it. For example, if you have 3 small paint jobs and 2 small carpentry jobs, it's better for you if you do 1 paint job, 1 carpentry job, another paint job, another carpentry job then the last paint job than to do these jobs in any other order. You'll get a better work out and let various parts of your body rest somewhat (my hand starts to cramp up on back to back paint jobs, for example).