I find few things match the old-school methods. Get in the habit of taking a bicycle instead of a car, for one thing. I swapped over to a bike this summer and I've seen an enormous change in my health and strength. I just got back from a run to three stores on the bike, about ten miles round trip across town. I left at two PM and got back at four PM, with a backpack and bike loaded with food. I've done that same three store trip (gun store, health food store, Freddies) many times in the car, and it also takes me about two hours. The bike allows me to cut across major detours, avoid the snagled areas and I can ride right to the front door. Plus when I get back I can have a pot pie without looking quite so much like a pot pie.
Hiking is also fantastic, as is skiing. For muscle builing I'd suggest building core muscles instead of trying to get big (and totally useless) biceps. Hatha yoga plus some core muscle weight training is a good balance.