THE SCIENCE OF SPEED LAND - PART 2

LAST ISSUE WE REVEALED THE RESISTANCE FORCES AT PLAY IN THE SWIM AND HOW THEY CAN BE OVERCOME VIA THE CORRECT TECHNIQUE AND THE RIGHT GEAR. THIS ISSUE WE HEAD TO DRY LAND, TO UNDERSTAND HOW YOU CAN BEAT DR AG AND HEAT ON THE BIKE AND RUN…

- JAMES WITTS 

You’ve exited the swim, shaken yourself down, pulled yourself out of your wetsuit and are ready to conquer the bike followed by the run. That requires generating power and reducing drag on two wheels, before holding a good pace on the final leg that won’t leave you firing up like an incinerator.

That might be the top line, but have you ever dug a little deeper into some of the physics and forces at play? Have you ever wondered why the faster you go, the more face-on the wind seems? Or why your tri-suit’s woven from a particular fabric? You have? Excellent news…

AERODYNAMICS MATTER

When it comes to the bike, and to a much lesser degree the run, aerodynamics count. This is one reason why: aerodynamic drag is cubic. What does that mean when seen through the prism of triathlon? Simply, that doubling your bike speed requires eight times as much power; in other words, the faster you go, the greater the air resistance. It’s why air resistance rather than friction, like from rolling resistance of your tyres, takes over as the dominant factor holding you back once you’re riding above around 16km/hr.