One of our readers wrote in with this question: I am an extreme biker. I bike six days every week and put in three thousand miles last year. I am in great shape. I am your superior. Signed, Extreme Bikers Rule.
Here's the answer:
I admit that you may have the edge on me when it comes to overall fitness. But I'd actually suggest you back off from the biking a little bit--or at least be sure to check with your doctor if you bike that much.
Believe it or not, studies have shown that men who engage in so-called "extreme biking" are frequently subjecting their testicles to trauma. Austrian researchers compared the men in a mountain-biking team with non-biking volunteers. They found thirty-five out of forty bikers had small injuries to their testicles. These injuries may be subtle, such as small cysts and calcium deposits, but they can become dangerous. Calcium deposits have been linked to testicular cancer, and that's no joke.
I'm not saying that: biking in general is very healthy. But the Austrian study suggests that, like anything you take to extremes, extreme biking puts you in a different category for risks. If you do it, you'll want to see a doctor regularly to make sure you're doing more good than harm.