I am 19 and have recently taken up running in order to get fit. However, I'm alarmed by the fact that if I run more than a few miles, my nipples bleed. This causes the appearance of two red "discs" on my T-shirt. It's worse on rainy days, when the cloth is damp. Help!

This condition is very well known among distance runners and it is called "jogger's nipple". Both women and men are affected by it. In fact, I used to get it myself in my half-marathon days.

It's caused by the friction of the running vest, rubbing against the chest. Many athletes recommend that, before going out to train, you should apply Vaseline or E45 to the nipple and the surrounding areola and then tape a small cotton wool pad over the whole area.