A little more relaxed now? You gotta love air. That blend of mostly nitrogen, some oxygen, with a sprinkling of argon, water vapor and carbon dioxide for good measure. It is this mixture of gases which provides the perfect environment for all kinds of animal and plant life to flourish. The more we exercise and the harder we attempt to move, the more precious this commodity becomes to us. Luckily, air is ever-present and we can tap into it whenever the mood to inhale strikes us. It is virtually impossible to avoid air.
However, while we take air for granted, it's actually quite fascinating stuff. For example, you might assume that it's virtually weightless and just "floats around", free of the influence of gravity. But that's far from the truth because it turns out that air is actually quite heavy.
If you had a cardboard box that was 3 feet on a side (height, width, depth), so a perfect cube, and you placed it at sea level with a temperature of 60 degrees F, how much do you think the air inside the box would weigh? The mass of air in the box would weigh about 2.5 pounds! Sounds crazy, I know. Since the pressure of air pushes equally in all directions, you're not aware of its weight or how much it presses against you every second of every day. It’s not even really noticeable when moving casually, such as when walking down the street or even hiking on a trail. But, start moving through it at an accelerated rate of speed, and the mass of air begins to be felt and to matter - a lot.
Nowhere is the impact of air resistance more palatable than while riding a bike – because this is the fastest form of human-powered locomotion in the world of Sport. Taking your “average-sized cyclist”, for every 10 feet ridden on the bike, the typical cyclist has to push 1.5 cubic yards of air weighing about 3 pounds out of the way. During an hour's ride averaging 18mph, a cyclist will need to push aside more than 20,000 cubic yards of air, weighing more than 40,000 pounds. That’s every hour!
In the light of the above, you can see why the largest component of power needed when cycling is to overcome drag force while moving through air. In a nutshell, the power needed to maintain a given speed on the bike is highly influenced by the rider’s velocity, but also of importance is how slippery the rider is when looking at the combined cross-sectional area of the cyclist and bike, and the drag coefficient (how aerodynamic or not that rider is). Since we cannot change the density of air, the only thing cyclists can do to make it easier to ride is improve the frontal profile they present to the wind. On a road bike, some adjustments are very simple – avoid loose-fitting clothing; keep the elbows in rather than flared out; ride lower rather than propped up; use slightly narrower handlebars that do not extend beyond shoulder width; if you’re flexible enough, increase the drop from your saddle height to your handlebar height by 1-2 centimeters. Just to name a few.
Tom Boonen of the Etixx-Quick Step professional cycling team, conducted some tests on an indoor velodrome a couple years back. He was very much a traditionalist, for example, always using box rim wheels for the Cobbled Classics – the Tour of Flanders, Paris-Roubaix and the other tune-up races. On the velodrome, he held a consistent wattage per lap as he made adjustments to his riding style. He changed things like his handlebar width, riding position and changing out the box rims for 50mm carbon wheels. The improvements in speed were staggering. With bars that were just 2cm narrower and changing to carbon racing wheels, he was able to push out 20-25w more at the same HR and effort. When he switched back to his old set-up, he cratered fairly quickly at the higher wattage. He was sold.
As athletes, we get so focused on training harder in order to improve that we overlook something that is quite literally right in front of us every day. Certainly, we have to train harder and smarter in order to improve. But, unless we optimize our riding position and equipment choices, it is also clear that a great deal of our improved fitness can simply be squandered away as we fight the ever-present friction and weight of the air around us.