Mireille Guiliano has some excellent advice on integrating exercise into your daily life. Although intended for women, there’s no reason to believe the same advice doesn’t apply to men. The short of it: Forget the gym and start moving around.
In 1975 I lost 50 pounds in 2.5 months while in Greece, never exercising a minute and eating anything I wanted. I wasn’t even aware I was losing weight and thought my clothing was stretching from over-laundering (stupid, huh?). The secret: I was alone with little money and walked 5-7 hours a day, camera in hand, seeing the sights. No taxis, no buses, just walking everywhere.