Knowing physics can help you improve your work out! I go to the gym a lot after school and everyone is always on the treadmills and a lot of people just walk with the incline of the treadmill up high. Some may think walking is a pretty easy work out and wont do much, but because of physics, if you add an incline or walk up a hill you actually are doing a lot of work. as you walk up a hill, the gravity pulling you towards earth's surface goes up which forces a person to do more work to walk up the incline. Because you are doing work against gravity you are burning more calories and exerting more energy. Another way physics can help you on a treadmill is by changing the frequency of your steps. if you do more steps in a shorter amount of time the frequency increases and the amount of energy your using and burning in that time also increase. Physics can help you anywhere.