Why is it often easier to start a fitness program than it is to maintain one?
A.
The motivation at the start of a program is often higher than later on when the progress made might be less obvious.
B.
At the start of a fitness program, the body is less used to physical activity so it feels better.
C.
Maintaining a fitness program decreases an individual's ability to sleep, making it more difficult to maintain a program than to begin one.
D.
all of the above