What sort of shape are you in? Are you the sort of person who goes for a run each morning, or are you the other kind who gets out of breath when reaching for a cigarette?
Maybe you have a lot of energy. You go to work or school, you make decisions all day, you do extra work at home. Exercise? You don't have enough time — why bother anyway?
Well, the answer to that question is your body design. Human beings weren't built for sitting at a desk all day: your body is constructed for hunting, jumping, lifting, running, climbing and a variety of other activities. If you don't get the exercise that your body wants, then things can go badly wrong. Your mind works all day, and your body does nothing: the results can vary from depression to severe illness to early death.
Not a very cheerful thought, and of course the natural reaction is "It's not going to happen to me." Maybe, maybe not. Here are two ways of looking after yourself: firstly, by seeing if you are doing the right sort of exercise, and secondly by seeing if you have the right kind of diet.
(From "Modern English International". Mozaika. 1984, No. 263)