Four years ago, Dutch duathlete Huub Mass was competing at world level in shorter events, but suffering diarrhoea and vomiting when attempting longer races. He approached sport and exercise

you were likely to face – before a single symptom struck? Sports physician Jack Taunton and exercise scientist Michael Ryan, both recreational runners from the University of British Columbia, Canada, were studying sports injuries four years ago when

you were likely to face – before a single symptom struck? Sports physician Jack Taunton and exercise scientist Michael Ryan, both recreational runners from the University of British Columbia, Canada, were studying sports injuries four years ago when