Marginal gains are important to cyclists. Riders ranging from Team GB athletes to steely-eyed commuters optimise their nutrition, equipment and positions just to shave a few seconds off their times.
So it’s no wonder that some MAMILs (that’s middle-aged men in Lycra) would also be interested in shaving their legs.
The theory is simple enough: removing the hairs on your legs reduces drag, the frictional force that applies resistance to any object moving through air. On a bike, air resistance is the number-one factor slowing you down (unless you’re riding uphill, in which case gravity is quite literally pulling you back).
As you ride forward, you displace the air molecules in front of you – that’s the ‘wind’ you feel. Aerodynamic design is all about optimising the flow of that air as it moves around you, to reduce the drag slowing you down.
It’s the reason why cycling helmets are shaped like sports cars, why riders wear skinsuits and why pro cyclists adopt a riding position in which their bodies sit as low and flat as possible over their bikes.
Could the hairs on your legs really make that much difference to your speed? That’s much debated among riders and engineers alike, but one study by bike manufacturer Specialized caught the eye.
Having shaved a rider’s legs, the research team tested him in a wind tunnel and found that his dolphin-smooth appendages reduced drag by a healthy 7 per cent.
Over the course of a 40km (25-mile) time trial, that saving would theoretically provide a 79-second advantage over an opponent with au naturel legs. Enough for a pro rider to seal a victory and to ensure you get the good spot in the bike rack at the office.
This article is an answer to the question (asked by Conrad Gordon, via email) 'I love nothing more than donning some Lycra and hitting the roads on my ultra-lightweight, professional-grade steed. Should I be shaving my legs?'
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