Though you see people doing them, Toe touches and calf stretches won’t prepare your muscles for a workout. The only way to warm up, say experts is with light aerobic exercise, walking, easy jogging or stationary cycling, for example. Do this for five to ten minutes and you are good to go. Muscles are like toffee- when cold, they are stiff and can tear if you over extended them. But they are pliable once the blood is pumping. In fact, you can save stretching for post -exercise.