Not only does exercise improve your health, even if you have already been diagnosed with something, but it can go a long way to prevent the onset of several life-threatening conditions, such as heart disease, diabetes and cancer. And exercise can make you look great - younger, fitter and thinner. Who needs any more convincing?

Think about it. A 30-minute walk every day can probably do more for your health than all the efforts of a dozen doctors and ten different types of medication.

The medical research points towards it: the fitter you are, the better your sex life is. The reason seems to be two-fold: psychologically you feel better about yourself and more inclined towards sex, and physically, being fit improves libido, blood circulation and sexual functioning. It has been said before that the brain may be the most important...