The offseason guide to aerodynamics by Michael Liberzon

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Winter is coming.

In this opinion of this coach and cycling aerodynamics enthusiast, winter is the best time to dial in your fastest position on the bike. Skeptical? Read on.

I am confident in saying that the majority of age-group triathletes of all skill-levels are not optimizing their riding position from an aerodynamic perspective. The most common argument I hear is that aerodynamic optimization is for high-performance athletes and is not relevant or is less relevant for middle-of-the-packers or slower folk. That simply isn’t true!

Let’s look at a comparison between three athletes racing at Ironman Mt Tremblant who were each able to lower their aero drag by 10%.

The pro

  • Original bike split of 4:21 at a coefficient of drag (CdA) of 220, and an average power of 260W
  • Optimized bike split of 4:12 at a very fast CdA of 200 (10% reduction) with the same average power, a savings of 9 minutes.

The ‘fast’ age grouper

  • Original bike split of 4:50 at a CdA of 250, and an average power of 240W
  • Optimized bike split of 4:40 at a CdA of225 (same 10% reduction) with the same average power, a savings of 10 minutes.

The middle-of-the-pack age grouper.

  • Original bike split of 6:00 at a CdA of 280, and an average power of 165W
  • Optimized bike split of 5:46 at a CdA of 250 (same 10% reduction) with the same average power: a savings of 14 minutes.

So while it is true that aerodynamics matter a great deal at high speeds, the total time saved by less-speedy athletes is actually greater!

So where do you find this 10%? On a recent episode of the Endurance Innovation Podcast, we hosted Cycling Canada aero geek Kurt Bergin-Taylor and asked him about his process of improving the aerodynamic performance of his national track team charges. Kurt presented a wealth of information, but his advice can be roughly boiled down to two key elements.

  1. Test to find your fastest position and setup
  2. Practice, practice, practice holding that position while including some work at race-relevant intensity

Testing

In the past, the only option for aerodynamic testing was the wind tunnel. Tunnel testing provided excellent, actionable results, but was prohibitively expensive. In practice, only pro athletes or those with a couple of thousand dollars burning those proverbial holes in their pockets had access to the service. Fortunately, this is no longer the case. With advances in field testing devices like ones from Calgary’s Aerolab and power-based apps like Aerotune, along with computational methods like the 4iiii Virtual Wind Tunnel, anyone interested in aero optimization now has accurate and affordable tools to do so.

The testing process itself is iterative. You assess the aerodynamic drag of your current position, make one change to your position or your equipment, and retest. It’s easy to see how finding the truly optimal can potentially take a lot of time, but it is entirely possible to find a very good position quite quickly by focusing on the variable most likely to make substantive aero impacts:

  • Head position
  • Hands and forearms
  • Race suit
  • Shoe and lower leg covers

Training

Now that you have that goldilocks position and setup, it is key to ensure that you can race in it. Hope is no substitute for a plan, and hoping that you can hold that aero position while pushing race watts for race-relevant time spans without training in it is a recipe for failure.

Here’s where my initial claim that the winter is ideal for dialing in your position comes in. Spend the last bit of decent, Southern Ontario weather to get your testing done, and then spend the winter and spring practicing holding that position. Indoor training is the perfect modality to get that done. This controlled environment, where you have the ability to set the intensity and duration and not have to worry about cars or other cyclists, is ideal for working on position.

Set up a mirror or a camera filming you from the side and watch that your head, hands, and shoulders are doing what they ought to be while you train. Approach positional training much the same way as you would an interval workout. That is, start with short intervals in position with relaxed or even upright recoveries. Over time, work on extending duration in position and reducing duration spent recovering. Eventually, you should be able to hold that pose for extended periods.

While it is important to include this positional training in your calendar, it should not be the only training that you do. Nor is it important to get up to full race duration without breaking position, especially if you’re racing long-course. In my opinion, the costs can often outweigh the benefits.

I hope you’re convinced. If you have any further questions about testing or training, do send me a note.

About the author

Michael is a mechanical-engineer-turned-triathlon-coach and founder of X3 Training. He has competed in all the common distances of triathlon and run everything from track to 50k. When he’s not coaching or playing with his kiddies, he co-hosts the Endurance Innovation Podcast.