Conscious contractions and releases of the pelvic floor muscles are commonly referred to as Kegel exercises. These are often recommended to pregnant women as ways of preparing for childbirth, but men can perform them too.
In men, they are often helpful for gaining control over urinary incontinence, preventing premature ejaculation and strengthening erections. Ordinary Kegel exercises are fairly simple and straightforward, but if you're seeking something more strenuous or challenging, there are some advanced techniques.
Before you can do advanced exercises, you must first identify your pelvic floor muscles and be able to perform a basic contraction. The best way to find your pelvic floor muscles, according to the Urology Department at UCLA, is to try to start and stop your urine stream while urinating. When you stop your urine stream, you're clenching the right muscles. Once you know how to clench your pelvic floor muscles, sit comfortably while squeezing and holding the muscles for five seconds, then relax. You may want to practice this several times before moving on to more advanced exercises.
Medical authorities like the Urology Department at UCLA recommend 10 to 20, 5-second flexes, with a short rest in between each flex, per set of standard Kegel exercises. Most also recommend three to four sets per day. This isn't too different from the advanced exercise suggested in Daniel Nixon and Max Gomez's "The Prostate Health Program: A Guide to Preventing and Controlling Prostate Cancer," but there is one key difference: intensity. A standard Kegel flex requires just enough of a squeeze to stop urine flow, as described in the above section. For a deep flex, squeeze as hard as you can, concentrating on the intensity. You may find this more achievable by performing this exercise lying down with your pelvis tilted slightly toward the ceiling. It may take practice to work up to 5-second flexes and 10-flex sets. Keep working until you can perform three sets of 10 per day.
A variation on Kegel exercises described in "The Everything Great Sex Book: From Sensuous to Sizzling, the Hottest Tips, Tricks and Techniques for Spicing Up Your Sex Life" by Suzie Heumann and Susan M. Campbell, Ph.D., requires you to have an erection. Start by standing up straight with an erection, and flex your pelvic floor muscles. You should see your penis rise and fall. Once you are comfortable with this, drape a sock or washcloth over the end of your penis and perform your usual set of 10 to 20 flexes. If you want more weight, use a wet sock or washcloth. Never attempt this with any significant weight.
This exercise, described in "Exercising The Penis: How To Make Your Most Prized Organ Bigger, Harder & Healthier" by Aaron Kemmer, Deby Cassill and Richard Howard II, involves coordinating your flexes with music. Once you have built up significant endurance with your pelvic floor muscles, you may be able to execute variable flexes for several consecutive minutes. A good way to keep the exercise beneficial and interesting is to play a CD and flex with the music, as if "dancing" with your pelvic floor muscles. It's best if the songs vary in tempo, so as to mix up the exercise. Break for several seconds whenever you feel the muscles getting tired, and try this with several different CDs over time. You can even do this while driving.