> The most widely cited test was a 1987 study for Bicycling magazine by engineering professor Chester Kyle, one of the pioneers of cycling aerodynamics. He found that leg-shaving reduced drag by 0.6 per cent, enough to save about 5 seconds over the course of one hour at the brisk speed of 37 kilometres per hour. At slower speeds, the savings would be less.
> [More recent tests in a modern windtulle show] that [shaving legs reduces drag] by about 7 per cent (...). In theory, that translates to a 79-second advantage over a 40-kilometre time trial that takes about one hour.
> [The aerodynamicists in charge of the windtunnel contacted Kyle], to ask if he had any ideas about the discrepancy between the two results. It turned out that the 1987 test involved a fake lower leg in a miniature wind tunnel with or without hair glued onto it – hardly a definitive test, and yet it was enough to persuade most people not to bother with further tests for the next three decades.
It's interesting because that would have been obvious to anyone looking at the methodology section of the original paper. Unfortunately it only takes one review paper or two paraphrasing or quoting the the original before it becomes standard lore (without the methodological caveats).
Interestingly, bicyclists have been shaving their legs anyway, ignoring the scientific consensus. Maybe common sense and personal experience is underrated.
Or cyclists like to shave their legs and want an excuse? Or shaved legs gives a psychological boost (more committed), is better for injuries, or when getting physio/massages; or a combination.
Edit:
It's curious to me, because in other areas it seems some degree of surface detail reduces drag (golf balls, aeroplanes too I've heard) - I wonder if short stubble is actually better and that's the effect you get using real legs. That would account for a plastic model only having a small gain.
I don't think this example generalises quite to that conclusion: as the tests show, the differences are huge, having bigger advantages than getting top-of-the-line bike equipment.
Assuming that we're already reaching the tail-end of the bell curve for human performance in cycling sport (which seems likely to me), suggesting minimal individual performance differences, then being at among that group despite a 7% performance disadvantage seems downright impossible.
So especially at the top there would be an incredible selection against anyone with hairy legs.
But I guess you could say that natural selection beats human belief.
> The most widely cited test was a 1987 study for Bicycling magazine by engineering professor Chester Kyle, one of the pioneers of cycling aerodynamics. He found that leg-shaving reduced drag by 0.6 per cent, enough to save about 5 seconds over the course of one hour at the brisk speed of 37 kilometres per hour. At slower speeds, the savings would be less.
> [More recent tests in a modern windtulle show] that [shaving legs reduces drag] by about 7 per cent (...). In theory, that translates to a 79-second advantage over a 40-kilometre time trial that takes about one hour.
> [The aerodynamicists in charge of the windtunnel contacted Kyle], to ask if he had any ideas about the discrepancy between the two results. It turned out that the 1987 test involved a fake lower leg in a miniature wind tunnel with or without hair glued onto it – hardly a definitive test, and yet it was enough to persuade most people not to bother with further tests for the next three decades.
https://beta.theglobeandmail.com/life/health-and-fitness/hea...