Kegels exercise the entire body of the pelvic floor muscles. These are the muscles responsible for erections strength, the ability to hold more blood, and this is very important as the penis becomes larger. With length and girth comes the necessity to fill those new areas with enough blood to keep good erection quality and the exercise that does this is Kegels. Also, once more is learned on Kegels and Reverse Kegels many special abilities may be realized like having an orgasm and not losing erection or multiple, male orgasm and other very cool effects. They are the silent majority of the health of your penis and should be done with as much effort as stretching or jelqing or any other pe exercise.