The Kona IRONMAN is fast approaching. For some exceptional triathletes, it is an annual event that cannot be ignored. But for a majority of those who will race it, it is the ultimate achievement, the culmination of many years of hard work and effort. Imagine all the hours invested in training!
Now imagine what you would need to do to increase your speed on the bike by 1 or 2km/h. You could spend a lot of energy training in order to increase your power output. Or better: you could increase your speed, without increasing your power, by decreasing your CdA. In a previous article, "What is CdA? And Why Is It Important As a Cyclist to Measure it? "Marc Graveline, co-founder of Notio Konect, explained very well the importance of the CdA.
Here are four tips that will help you lower your CdA with Notio Konect and be more efficient especially for the upcoming IRONMAN World Championships.
Generally speaking, the cyclist with his position, helmet and clothing is responsible for 80% of the air resistance that must be overcome to advance. The bike accounts for 20%. It is generally much more beneficial to invest time to improve your position and your CdA than to change wheels for example. Moreover, it is surprising to see certain elements (i.e. position) in professional triathletes and cyclists who defy any theory whereas their CdA is optimal.
It's a debate that comes up every year because of the extreme heat and humidity conditions in Kona. What is ideal? Wearing an aero-type time trial helmet or opt for a more ventilated helmet? If there is one accessory that has the greatest impact on the CdA, it is most probably the helmet. Even if there are helmets that will very often perform well from an aero point of view, the final results depend on the position and shape of the cyclist. Sometimes the final results are surprising! Often, the more ventilated a helmet is, the less aerodynamic it will be. In this case, it is a compromise between how much watts an athlete is willing to sacrifice to ventilate his heat VS tolerance.
© Photo: X3 Training
Clothing has a significant impact on the CdA, as it determines the cyclist's friction with air. Manufacturers have become very ingenious in the use of fabrics that offer a lower air resistance than the skin, hence the appearance of triathlon suits with sleeves. But no matter the price, you should always favour a triathlon combination that fits "well", i.e. fitted and does not pocket or crease.
Today, triathletes have access to countless hydration options: aero-extender hydration systems, hydration systems integrated into the frame, aero bottles, 1 or 2 bottles in the frame front triangle, behind the saddle bottle holders, etc. Knowing that the results on aerodynamics will depend on the bike, the rider's position and that these accessories are part of the 20% air resistance coming from the bike, the best thing to do is to use a system that allows you to keep your optimal position most of the time while hydrating.
In short, as you've read this piece, you've probably noticed that there is no magic recipe for being more aero. If there is only one thing to take away from this article, it is the following: the combination of cyclist, bike and accessories creates a unique system where all elements are linked. Therefore, each person doing real-time aerodynamic tests will have different results. Hence the importance of testing and measuring with Notio Konect to optimize performance.