Riding a bicycle is a great cardiovascular workout and can be very enjoyable for those who participate in this sport.  For men who regularly ride a bicycle to keep fit and especially for men who ride dozens if not hundreds of miles competitively, they may find themselves concerned with the effect of this activity on their prostate specific antigen or PSA levels.  Because of the direct pressure on the prostate and perineum (the area between the scrotum and the anus when sitting on a bicycle seat), some researchers have speculated if this could result in an elevated PSA. 

Prostate gland and PSA

The small, walnut-sized prostate gland is responsible for the production of semen and it located below a man’s bladder.  PSA is a protein secreted by the prostate gland that’s often elevated if a man has a prostatic disease, including prostate cancer.  This is why middle-aged and older men are strongly recommended to have regular PSA screenings by their doctor.  A PSA test measures the amount of the antigen in the blood and if the number is elevated, it could possibly indicate an enlarged prostate known as benign prostatic hyperplasia (BPH) or prostate cancer. 

Studies on PSA levels and riding a bicycle

An early study conducted back in 1996, had researchers measure the PSA levels of 260 volunteers before and after a four-day 250 mile bicycle ride in the Colorado Rocky Mountains.  After the volunteers had completed their ride, none of the men had any significant increase in their PSA levels with the exception of four men who had an already elevated PSA before they started.

Even in the men whose PSA levels were already elevated, the difference was modest and was not enough to influence anything.  The takeaway from the research was that if bicycling did cause trauma to the prostate that make a significant difference in PSA, the study would have found it. 

Since the study in 1996, there have been a few other small studies looking into this very topic.  One study done in 2004 on long-distance bicycling, found that in 42 healthy male cyclists, the measurement of PSA is not disturbed by participating in long distance bicycling or endurance exercise.  The researchers recommended that there was no evidence a man would need to limit bicycle riding or physical activity before a PSA test. 

A 2009 study found there to be no effect of rigorous or professional bicycle riding on serum total PSA levels of 58 male participants. 

The most recent study done in 2015, a systematic review and meta-analysis consisting of eight studies comprising a total of 912 male participants, found no effect of cycling on PSA.  However, the median sample size consisted of only 42 subjects giving the study a low statistical power to detect a difference in PSA. 

To bicycle or not

The answer to the question does bicycling affect PSA or not, it appears from the few studies that have researched this topic, the answer is most likely not.  It appears that men, who enjoy bicycling for exercise and pleasure, can continue to do so.  Whether bicycling is done outdoors, indoors on an exercise bike or in a spin class, it does not seem to make a difference in affecting a man’s PSA levels.  It would be recommended however, for a man who is getting ready to have his PSA level checked, to discuss with his physician if he needs to refrain from bicycling a day or so before the test.  This might help ensure a more accurate measurement.