The prostate gland sits beneath the bladder in men and surrounds the urethral tube, which lets urine pass through the penis and out of the body. In some cases, overgrowth or enlargement of the prostate triggers a variety of urination-related problems. Doctors don't know exactly what causes this enlargement, but aerobic exercise is not indicated on the list of potential factors.
Basics
Your prostate gland produces semen, the fluid that carries and protects your sperm as they pass from your testicles through your urethra during ejaculation. When boys enter puberty, the prostate gland grows to roughly double its original size. A second, slower growth of the prostate begins in the mid-20s and continues throughout adulthood. It is this second growth phase that leads to an enlarged prostate in some men. This condition is known as benign prostatic hyperplasia, or BPH.
Lowered Testosterone
While doctors don't know precisely why BPH occurs, they have developed several working theories on the condition's origins. One theory links BPH to common hormonal changes. In addition to testosterone and other classically "male" hormones, men produce small amounts of the "female" hormone estrogen. As men grow older, testosterone production decreases, while estrogen production remains more or less constant. According to this theory, the increasing proportion of estrogen triggers heightened activity in certain substances that encourage growth of prostate gland cells.
DHT and Cell Reactivation
The onset of BPH may also be related to the activity of another hormone called dihydrotestosterone, or DHT, which is produced in the prostate gland as a byproduct of testosterone. Even when testosterone production falls off in later life, DHT continues to accumulate inside the prostate. In time, this DHT buildup may trigger the onset of an enlarged prostate. In fact, men who don't produce DHT never experience prostate enlargement. A third theory on the origins of BPH indicates that the condition may result from a reactivation of certain cells inside the prostate that send out growth instructions.
Considerations
Despite its identity as an abnormal condition, BPH might eventually appear in all men if they lived long enough, according to MedlinePlus. In fact, more than 90 percent of men past the age of 80 have some form of the condition. In addition to advancing age, the only known risk factor for the onset of BPH is the presence of testicles that function properly. When men have their testicles removed at a relatively early age, they don't develop enlarged prostate glands in later life. More than half of men with BPH don't have any symptoms related to their condition. Consult your doctor for more information on BPH and aerobic exercise.
