Gabe Mirkin, M.D.
Training for sports is done by exercising hard, feeling sore on the next day and then taking easy workouts until the soreness disappears. When your muscles feel fresh, you take another hard workout again. Most competitive athletes work on a program in which they take three or four easy workouts for every hard one. An article in the journal of the American College of Sports Medicine shows that athletes recover faster when they exercise and barely move with little pressure on their muscles than when their exerted muscles are immobilized.
Even if you exercise only for fitness and not for competition, you can take advantage of this information by taking easy workouts on alternate days rather than taking days off. Take a hard workout on one day. The next day, if your muscles are only a little sore, take an easy workout with no pressure on your muscles. If you are a runner, run fast on one day, then walk or jog at a very slow pace the next day or for several days until your muscles are fresh again. If you are a bicycle rider, take a very hard long, fast workout on one day. The next day, if your muscles are not too sore, spin with no resistance on a stationary bicycle. Any time your muscles are very sore you should take the day off to prevent injury.