2021 Ironman World Championship St George bike course analysis

It is time! After cancellations and delays due to the Covid-19 pandemic, the Ironman World Championship is back, but this time with a twist.

The delayed 2021 Ironman World Champs will take place this weekend in the fittingly difficult location of St. George, Utah. For those who think the race loses some appeal taking place outside of Kona, rest assured the course and competition will be up to the challenge. While some of the significant players are out of the race, including defending champs Jan Frodeno and Patrick Lange as well as favorites Lucy Charles and Laura Philipp, there are several rookie contenders who have been posting seemingly insurmountable training numbers. With many fan favorites and some dark horses, we expect this race to live up to the typical World Championship hype.

Our race preview will focus on the course and how it differs from Kona. We are not planning on posting our traditional predictions this year but instead will look at the tactics different types of athletes could use to play to their strengths. With that, let's dive into the course details.

The Course

While different from Kona, the St. George course is no less challenging and arguably more so with significantly more climbing. Often the pros at Kona can reap benefits against the infamous winds due to early start times and getting legal drafting benefits. There is no hiding from the climbs at St. George, with most of the climbing happening in the late stages of the bike on tired legs. Expect any significant separation moves on the bike around mile 100 up the snow canyon climb before a fast descent back into transition. Not to be discounted is that St. George is a much higher overall elevation. Many of the favorites have been training in similar or even much higher altitudes to prepare and should feel comfortable whereas those training at sea level could feel a bit sluggish.

Elevation St. George vs Kona

The Weather

Another critical difference between the two courses is humidity. Kona averages in the mid to upper 80 percent for humidity, whereas St. George will be around 15% on race day. Dry air is a bit slower aerodynamically; however, some favorites have suffered more in a combination of high heat and humidity. This has resulted in lower overall average power output. The wind should not be a significant factor. However, there is still a legal draft aerodynamic advantage in the flatter early sections of the course.

Weather at St. George

The Race

Interestingly, when all things are considered, the estimated bike splits for similar power values between Kona and St. George are roughly the same. The course should, in theory, favor the strong riders, given there is more overall climbing and a smaller legal draft advantage. Potentially more so than even the great Kona course, St. George will be a true testament to each athlete's individual potential.

Check out our 2021 Ironman World Championship race plan and use the Time Analysis tool to set your own drag, power, weight and rolling resistance. What kind of bike split would you have on race day?

Weather at St. George

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