Finally, flexibility is a major component of physical fitness that is often overlooked.

Overworked and tight muscles are uncomfortable and can eventually cause postural problems, which is why you should always stretch muscles thoroughly (10 to 20 seconds for each muscle group) after every exercise session. This will help keep your muscles in healthy balance with a full range of movement.

Stretching before you do a workout is also important, since it prepares your muscles for the work they are about to do, and this should ideally be done after having gently warmed the body (with a brisk walk, for example).