The Stitch
A masters racer I work with came to me with a strange problem. Ten minutes into any hard effort — didn't matter the bike, didn't matter the position, climbing upright or buried in the drops — a sharp, gripping pain would knife into his side and shut the effort down.
The consistency was the tell. If it were a fit issue, it would've shown up differently on different bikes, different positions. It didn't. Same pain, same timing, every time.
What he has is something sports medicine still can't fully explain: exercise-related transient abdominal pain (ETAP), or what you've always just called a side stitch. It shows up far less in cycling than in running or swimming, but it's the same beast, and researchers have spent decades circling three competing theories for why it happens: your diaphragm losing blood flow under load, tension pulling on the ligaments that anchor your organs, or straight-up irritation of the lining around your abdominal cavity. Nobody's proven which one wins. Possibly all three do, in different riders.
Since the mechanism is still up for debate, there's no single fix. But a couple of things are worth trying if this sounds familiar:
Retrain the breath. The stitch shows up more in "chest breathers" — riders taking short, shallow pulls high in the ribcage instead of driving the breath down into the belly. A simple drill: lie on your back, put a book on your stomach, and practice making it rise and fall instead of bracing your ribs. Do it for a few minutes a day off the bike.
Rethink your pre-ride fueling. It's more common after eating or drinking close to a hard effort, especially anything sugary or concentrated. Try moving your last meal or bottle earlier, and lighter, before your hardest work.
My rider is still working through this, integrating some breathing work into his routine. That 10-minute wall will likely still show up, but hopefully to a lesser degree. We’re learning more about the issue, he's got more tools now than he did a month ago, and that’s usually where these things start to give way.
See you next week,
Steve