Pugh also showed that at the speeds at which middle-distance track events are run (6 m/s or about 67 seconds per 400 m), about 8% of the runners energy is used in overcoming air resistance. But by running directly behind a leading runner (or drafting) at a distance of about 1 m, the athlete can save 80% of that energy. In a middle-distance race this would be equivalent to a savings of about 4 seconds per lap. However, Pugh considers it unlikely that in practice the following athletes would ever be able to run as close to the lead runner to benefit to this extent.
Photo Gallery of Core Yoga Poses
Click to on Photo for Next Core Yoga Poses Images
By running slightly to the side of the lead runner, the following runner would probably benefit by about 1 second per lap (Pugh, 1970a, 1970b).
Another researcher to study the benefits of drafting was Californian Chester R. Kyle (1979). His calculations suggest that at world-record mile pace, a runner running 2 m behind the lead runner would save about 1.66 seconds per lap, which generally confirms Pughs estimations. Kyle calculated that the benefits of drafting in cycling are much greater than in running, some 30% or more. In addition, the larger the group and the farther from the front the cyclist rides, the more the cyclist benefits.
In contrast, the aerodynamic drag is increased when runners are positioned abreast because the larger frontal area results in a larger shared drag (L. Brownlie et al, 1987a).
These findings explain why track athletes find pacers to be such essential ingredients in aiming for world track records. In addition, these findings explain why world records in the sprints are set at altitude. During sprinting, the energy cost of overcoming air resistance rises to between 13 and 16% of the total cost of running. Thus, the sprinter benefits greatly by running at an altitude where air resistance is considerably reduced. It is interesting that when a runner is racing on a circular track, an optimum strategy is to accelerate into the wind and to decelerate when the wind is from behind, the opposite of what one would expect (Hatsell, 1974).
The Briton Dr. Mervyn Davies (C.T. M. Davies, 1980c, 1981) extended Pughs findings. Davies used essentially the same techniques as Pugh but included observations on the effects of downhill running and of following winds of different speeds.