Unofficial Ironman® Boulder 411 Page

Welcome to the Endurance Nation Race Strategy page for Ironman® Boulder!

Endurance Nation is five-time Division One Global Ironman® TriClub Champions — no team on the planet has raced more often or as fast as Endurance Nation. Explore this page for some of our guidance, head over to the EN Blog or consider signing up to train & race with us. Plans start at just $47!  Click here to pick the right option for you 

Our goal here is to get you 100% up to speed and ready to have your best race possible. Every single race is unique, and Ironman® Boulder is no exception. Please review these resources and Boulder insights to prepare for your big race!

Three Bullets Video | Detailed Race Info | Equipment | The Swim | The Bike | The Run | Free Trial

Three Bullets on Ironman® Boulder

Don’t have time time to dive into a full review of the course? Then cover the most important highlights in this short video with Coach Rich from Endurance Nation. Finally, be sure to watch Coach Rich’s Ironman Boulder bike course overview below, where he delivers valuable guidance for racing at altitude. 

Detailed Race Information

Equipment Recommendations [top]

Temperatures are generally mild for Boulder in June, though it may be chilly at the start of the race and winds are sure to pick up on the bike. And high altitude areas cool down quickly after sunset so be prepared for that as well.

The Swim: Bring everything you need. Tinted goggles also recommended. 

The Bike:  We recommend a triathlon bike with all of your aero wizardry applied: front race wheel, rear disk (or wheelcover), aero helmet, race tires, smart bottle and equipment placement, etc. 

For gearing we nearly always recommend a compact crank (50/34) or “super compact” (52/36) if you’re a bit of a stronger rider on an 11 speed bike. Everyone should have at least a 25t cog on their cassette, with less strong riders always benefiting from a 28t or higher (for example, a 28-12 cassette).

The Run:  You will want to choose gear that will give you flexibility to handle the heat, if a hot day is in the cards. It will need to have pockets for carrying nutrition, and plenty of zippers so you can reduce any accumulated heat. A hat is recommended, of visor at a minimum. 

If you aren’t carrying your own fluids with you, then plan on transporting salt at a minimum so you can keep your gut happy. Plan on a race number belt with pockets to carry salt / fuel. You can access your Run Special Needs bag only at the beginning of the second loop.

Swim Course Breakdown  [top]

The Ironman® Boulder swim is a single loop, and you will not be swimming into the sun at any portion of the course. You will seed yourself in the chute according to your projected swim time.

>> View the online swim map here

Key Points:

  • Bring a wetsuit, as well as a neoprene hat and perhaps booties, as you can expect the water to be cold in early June.

Bike Course Breakdown [top]

The Ironman® Boulder bike is three loops, as one loop to the east that you do once before heading north and doing the “main loop” twice. The terrain varies from flat to rolling so be sure to learn how to ride hills smoothly and efficiently. Review Coach Rich’s Three Bullets video above for our complete hill climbing guidance, and be sure to watch his detailed bike overview video below.

>> View the official bike map here.

Key Points:

  • Ride very easy, ignoring everyone around you, until about mile 15 or 20 of the bike.
  • From there, just execute the terrain in front of you in a manner that sets up the run.
  • If you need to go from the aerobars to the hoods, due to crosswinds, stay low and hide from the wind!

Run Course Breakdown [top]

The Ironman® Boulder run course is two loops with 3 out and backs on each loop. Be prepared for a climb from miles 20 through 24!

We recommend you give yourself 6 miles of easy running to settle in, getting a head start on your nutrition and hydration. From there, run comfortably, getting what you need at the aid stations and preparing yourself mentally to dig deep after mile 18.

>> View the Run Map here.

Key Points:

  • Run stupid easy the first 6 miles.
  • Stay focused on your pacing, nutrition, and hydration in the lonely parts of the course.
  • Be prepared to step on the gas at about mile 21 or 22, finishing strong!


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