I can’t seem to run anywhere without getting a stitch. How can I stop it happening?
Rob Wallace, via email

Matt Hart replies: Despite any theories you might have heard, scientists have never really been sure what causes the stitch. Recent research suggests a stitch is likely to be caused by the weight of food or fluid in the gut pulling on tendons attached to the diaphragm. Even if this isn’t completely correct, the best way to prevent a stitch is to avoid eating or drinking much within three hours before exercise. When you get a stitch, bend forward and tighten your abdominal muscles, while breathing out through pursed lips. Try wearing a light wide belt around your waist to support your gut. If you always exhale when your right foot strikes the ground, try exhaling when your left foot hits instead.