When a running niggle needs a visit

Most aches fade if you cut back for a week. A simple traffic-light rule helps you tell which ones will not.

Almost every runner has something that twinges. The hard part is knowing whether to keep going. Jonas gives his runners the same simple rule, based on a score from zero to ten during and after a run.

Green: zero to three

Keep running. The ache is mild, it settles within an hour, and it is no worse the next morning.

Orange: four or five

Cut your distance by a third for a week and drop the fast sessions. Swap one run for cycling or swimming, then build up again gradually.

Red: six or more

Stop, and book a visit if any of these apply: you limp, the pain wakes you at night, there is one exact spot on the bone that hurts when you press it, or the pain is still there after two weeks of cutting back.

Most running injuries come down to doing a little too much a little too soon. They rarely mean you have to stop for good, and an early visit usually means a shorter break.