The sceptical medic

Ask Dr Nick

How long should you leave between eating and exercise? I like to go to the gym before work and I never know whether to eat breakfast before or after.

Anyone who exercises regularly does not need a doctor to tell them that eating just before a workout may cause difficulties. The consequent indigestion, nausea and a stitch are painfully familiar to us all, and result from exercise-induced slowing of the bowels and relaxation of the closure of the stomach. Activities most likely to cause such symptoms involve running, jumping, changes of direction and high intensity (such as football, rugby and tennis).

But having some carbohydrates on board is necessary. For routine training, a piece of toast, a small bowl of cereal or liquid food one or two hours before exercise will suffice. If you want to train immediately on waking, have a reasonable dinner the night before, to maintain energy stores, then have a carbohydrate drink (even a cup of tea with sugar), an energy bar or piece of fruit first thing.

If you plan to exercise within an hour of a substantial breakfast, certain conditioning programmes, weights and aerobic activities such as cycling and rowing may be manageable. Avoid a cooked breakfast (high fat products and red meat) due to the slow absorption time. If you are training hard or are in competition, a 'pre...#8209;event meal' may be needed three or so hours in advance: easily digested carbohydrates such as porridge, cereals, pastas, rice and potatoes, and 'light meats' such as chicken and fish.

· Dr Nicholas Peirce is the ECB's chief medical officer and a lead physician for the English Institute of Sport. To ask aquestion, email