A study published last year found that watching too much TV may lower a man’s sperm count, but in reality, I don’t see it that way. However, there are five environmental factors that have indeed been shown to decrease sperm count

Researchers found there was an association – not a direct link – between individuals that watch TV more than 20 hours a week, focusing on the level of inactivity, and having a lower sperm count compared to men who exercised regularly.

This association has to do with previous findings, which have shown that weight and muscle mass have a direct effect on male hormones, like testosterone.  This impact, in turn, could alter your sperm count.  So there’s not really a direct link.

However, there are five environmental factors that have indeed been shown to decrease sperm count.

1. Industrial chemicals, such as benzenes, herbicides, pesticides, and certain painting material

2. Heavy metals, especially lead

3. Radiation or X-rays to the pelvic area

4. Overheating, such as frequent use of saunas, hot tubs, and yes – computers in your lap.  They overheat your testicles and decrease sperm production

5. Prolonged bicycling.  For all those guys who like to bike, watch out because this could be doing some damage to your sperm

Of course, there are other more medically oriented reasons that can impact sperm count, such as varicocele – the swelling of veins which drains the testicle.  Also infection, especially from sexually transmitted diseases like chlamydia and gonorrhea, can decrease semen virility.

Dr. Manny Alvarez serves as Fox News Channel's senior managing health editor. He also serves as chairman of the department of obstetrics/gynecology and reproductive science at Hackensack University Medical Center in New Jersey. Click here for more information on Dr. Manny's work with Hackensack University Medical Center. Visit AskDrManny.com for more.