Question: I’m a new rider and have improved rapidly. I raced a criterium last weekend and it felt like my lung and rib were attached when I reached a high exertion level. This made it very hard to breathe. My friends told me it was a “stitch.” Can you shed light on this? — Keith H.
Coach Fred Matheny Replies: The cause of side stitches is in doubt, but the most compelling explanation I’ve heard is that they’re caused by cramping of the diaphragm muscles.
When you breathe hard for long periods, such as when trying to stay with the pack in a crit, the muscles are overworked and go into spasm, causing the cramp-like pain you feel.
The solution is to include high-intensity efforts in your training. You need to accustom your diaphragm muscles to rapid deep breathing.
Usually, stitches are more prevalent in early-season races or, as in your case, during first attempts at racing. Once training and racing conditions your body to the exertion, the stitches should go away.