Want free speed? Lose the hair.
Working in a triathlon shop, we get all kinds of customers. We deal with every type of athlete, from the Type-A personality triathlete with the latest and greatest equipment, to the working college student scraping by with hand-me-downs and clearance rack items. But one thing that oddly seems to tie them all together is this: no leg hair. The vast majority of triathletes shave their legs! Personally, I thought it was just to show off at first. (I'll be the first to admit I like how my legs looked post-ride sans hair; sweat dripping down my rippling calf muscles, quadriceps bursting at the seams, the longing look of ladies and lads as I lazed about enjoying a hoppy post-ride recovery beverage...)
But I digress...
For many, many years, cyclists (and triathletes by extension) have been told to shave their legs and have been given different reasons for doing it; it makes massage easier, cleaning road rash is easier, showing off your muscles to intimidate your enemies and crush their willpower is easier, etc. But one reason that was generally brushed off to the side was that it makes you faster. But why was it brushed off? Any weight loss from shaving was insignificant. Was drag not noticeably reduced with smooth legs?
Here comes the science! There was a study done in 1987 for Bicycling magazine by Chester Kyle, confirming a 0.6% aerodynamic advantage, which basically equates to a 5-second time difference in a 40 km race. Yup, no real advantage. And since renting out wind tunnels isn't exactly the most affordable thing a researcher can do with their grant money, the subject wasn't really touched upon again or peer-reviewed. That is, at least, until a bicycle company found themselves with a wind tunnel, a freshly shaved athlete, and too, too much time on their hands.
Specialized engineers have been using the WIN Tunnel, their custom-built wind tunnel housed at their headquarters in northern California, to test frames, wheels, athletes' positions, helmets, etc. When one of their sponsored athletes showed up and had to shave in preparation for his upcoming season of triathlons, he wanted to get tested. So he did. That resulted in Specialized engineers actually doing a study with multiple athletes that found an average of 70 seconds saved over a 40km race.
The savings extend to other sports, too. A 1989 study published in the academic journal, Medicine and Science in Sports and Exercise, found that shaving the hair off of arms, legs, and exposed trunk reduced active drag and reduced the physiological cost of swimming. If you're looking for what the time savings were, that info was not published, as the researchers used distance per stroke as a metric for the study, rather than time.
And finally, what about running? Does shaving have any effect on runners and their times? Unfortunately, I could not find any studies done regarding runners and shaving. Sorry about that. But hey! Two out of three ain't bad, right?
So what have we learned today? If you want to be faster for the low, low cost of free, get shaved. It may not be enough to win your next race, but who's to say a new PR is out of reach?
Questions? Comments? Cheap shots? Let me know. Thanks for reading!