Note that males can also do kegels. A simpler term for understanding them may be penis push-ups; you contract your pelvic muscle group and, if your member is erect, this will manifest itself in movement. It's the exact same thing as a kegel in females (after all, the sexes are just slightly different, physically), and assists in bladder control and ejaculation strength. They're known to enhance penis size too; consider it if you want an upgrade. Do them in sets when bored!