Yesterday in the free AM newspaper in New York City was an article on the physical benefits of playing soccer. Exercise physiologists conducted a study that showed that soccer players have the best bodies out of a group of other sports players.
I often thought that soccer must be the most physically-demanding sport. That is because you continually running. In baseball and football, there are breaks. In basketball and tennis the field is not as big as the one in soccer. Although you don't use your upper body as much as your lower body in soccer, the interval like movements of start and stop and the plyometric movements of bending your knees to avoid opponents or get to the ball add to the extremeness of the sport and to the workout.
My third book, Pocket Guide to Fitness, is available on http://www.authorhouse.com and http://www.amazon.com. If you look up my name on those Web sites, you will find my other books The Boy in a Wheelchair and Life, Work and Play: Poems and Short Stories. These two books are on my Web site http://www.louizapatsis.com.