Aerodynamics to cycling, aero gains

It’s only relatively recently that the importance of aerodynamics to cycling has become fully realised. Whereas once riders were looking for the lightest kit and components available, it’s now known, in most riding scenarios, that aero trumps weight. Aero for cyclists is all about overcoming drag. Drag for a cyclist can be measured and expressed by a figure known as CdA. ‘Cd’ is the coefficient of drag.

This is the resistance created by an object or shape when moving through the air. For example, a traditional round seat-tube will have a far higher coefficient of drag than an aero teardrop-shaped one. ‘A’ is the frontal area you present to the wind while moving forward on your bike. Aerodynamics are so important because the relationship between drag (expressed as CdA) and speed isn’t linear. Simply put, doubling your power output doesn’t double your speed or we’d see Tour de France sprinters battling for the line at over 250 kph.

The reason this doesn’t happen is that most of the energy you put into your pedals is used overcoming air resistance, hitting air molecules and punching them aside. As you go faster, not only are you hitting those air molecules harder but you’re also having to push through more of them every second.

In the British Cycling ‘Secret Squirrel Club’, we were well ahead of the aero curve, spending hours testing in the wind tunnel, making mannequins of team riders and producing skinsuits so effective that the UCI banned them. However, for all the go-faster aero kit and equipment, the rider is accountable for 70–80 per cent of drag. If your position on the bike isn’t aerodynamically optimised, you can’t hold that position or it saps your power, you’re wasting hard-earned watts and giving away speed.

Obviously, if you’re targeting time trials or pursuit on the track, being able to get and hold aero is key, but it’s also vital for road racers. Less obvious, maybe, is the importance for sportive riders. If you’re able to hold an aero position and therefore expend less energy for the same speed on the flat, you’ll have more left in the tank for climbs. Being able to get down and hold a position on your drops means faster and safer descending. Finally, in those last couple of hours of a gruelling ride, if you’re not having to continuously sit up and stop pedalling to stretch your back out but can hold a strong aero position, you’ll save significant time.

30 min Indoor Cycling Class

With all bike fits and positioning, the bike is infinitely adjustable and the rider is finitely adaptable. Often, because of the physical limitations of the rider, the bike has to be tweaked to accommodate these limitations, but this will always tend to involve compromising aerodynamic efficiency. Therefore, if you’re able to adapt your body using the correctional exercises in this book, you’ll be able to adopt a more aero position and hold it for longer. Over the last ten years we’ve managed to identify the key areas you should be working on and it’s no coincidence that these are key areas of the assessment and subsequent exercises.

By focusing on these correctional exercises to improve your range of movement, you’ll improve your ability to attain a more aerodynamic position on the bike. However, this isn’t the end of the process and by working on your control and strength through that range of movement, you’ll be able to sustain that position for longer, more stable in it and able to produce more power.

Shifter, Chainring, Brake, Derailleur