Stomach problems

Stomach trouble while running is common: blood is diverted from the gut and the jolting shakes it, which can bring nausea, cramps or an urgent need for the toilet (runner’s trots).

• Common triggers: eating too close to the run, fatty, fibrous or spicy food, lots of coffee, dairy, gels without water, dehydration, nerves.
• Have your last meal 2 to 4 hours before, low in fibre and fat, and cut fibre the day before a race.
• Take gels with water, and train your gut by practising your fuelling on long runs.
• Go to the toilet before you start, and slow down when cramps come.

See a doctor if there is blood in your stool, pain between runs, weight loss, or symptoms at every run.