toward home. Two hours, nothing to it. When I want to increase my training prior to a marathon, I just add another 9/1 segment on the outbound trip. Now the session lasts two hours and 20 minutes, and I hardly notice the difference. Two weeks later, I do

this first-hand on a 1998 trip to Kenya. One morning, I joined a handful of marathon runners who were being coached by Dr Gabriella Rosa as they tackled the infamous Fluorspar Hill that rises nearly 4000ft in 13 miles.I managed to hang on for only 10 minutes

therapist and biomechanist Irene Davis from the University of Delaware's Running Injury Clinic. "Your threshold could be at 10 miles a week, or 100, but once you exceed it, you get injured." Various studies have identified injury thresholds at 11, 25, and 40

of the participants running a 62-mile race consumed 14,000 millilitres of liquid; another who ran only 26 miles, drank only 280 millilitres. The latter runner, not surprisingly, showed the most loss of vascular fluid, resulting in thickened blood plasma and impaired