In the past, most people used to get enough exercise in their work and life to stay reasonably fit. But nowadays, an increasing number of people work in offices and factories, and many jobs involve mental work. They sit down most of the day. Thus their work does not provide them with enough exercises their bodies need. More and more people have come to realize that it is important to do regular physical exercises in order to keep fit. Good health is based on regular exercises. Exercises tire the body but then actually give people more energy, make people stronger. So now we can see many people, especially old people, take an active part in different kinds of exercises everyday.