Amby Burfoot is Executive Editor of Runner's World USA, and the 1968 Boston Marathon winner Imagine that there was an exercise programme that could guarantee to get you in shape with only three identical 30-minute exercise sessions per week. I
of running not mileage totals, not your marathon PB, and certainly not the percentage of VO2 max you can maintain when running at lactate-threshold pace while holding your breath on a treadmill set at a six-per-cent-incline in a hypoxic tent. These Zen
on treadmills, not of cyclists. No one can say exactly how the two differ, but they do. The triathlon legend Mark Allen has lived in those narrow spaces. Allen is the fastest runner ever to win six Hawaii Ironman Triathlons. In 1989, he closed with a 2
