Heat Training Strategies for Summer Ultras: Insights from Western States Legend Megan Canfield

As race season heats up in the Northern Hemisphere, so do the temperatures - and with that, the physiological demands of endurance running rise dramatically.

Western States legend Megan Canfield knows a thing or two about performing in high heat. With ten top-10 finishes at the Western States Endurance Run, Megan has mastered the art of racing smart when temperatures soar.

In this special guest feature, she shares tried-and-tested strategies for preparing your body for extreme conditions — and why adding CurraNZ to your protocol can provide additional support.

Why Heat Training Matters - by the Queen of Western States

Megan writes: "Summer ultra races often come hand-in-hand with oppressive heat and humidity - a challenge that many runners underestimate. The seasonal weather transition often coincides with an increase in race schedules, which adds another variable an ultra-runner needs to anticipate and prepare for. 

Fortunately, the body is brilliant at adapting to hotter environments over time from higher temperature exposure. With the right heat training, you can prime your system to perform more efficiently and recover faster in extreme environments.

Here’s what heat acclimation can do:

• Increase sweat rate – cools the skin via evaporative cooling
• Accelerate sweating onset – the body anticipates getting hot
• Lower core temperature – both at rest and during exercise
• Increase blood plasma volume – facilitates increased sweat volume, with the benefit of altitude-like benefits
• Reduce electrolyte loss – creates a more dilute sweat, so you hold onto your salt
• Improve cardiovascular stability – driven partly by increased plasma volume
• Enhance skeletal muscle metabolism
• Increase heat shock proteins – supports cellular protection and adaptation

How to Heat Train Smart

According to Megan, 7-10 days of dedicated heat training is typically enough to bring on these adaptations - and they can be maintained with a session every 2-3 days thereafter.

Megan’s tried-and-trusted methods:

Passive heat training in a dry sauna.
Start with 20 minutes in the sauna immediately after your running warm-up (when your core temperature is already elevated), and let the sauna do the rest for 20 minutes. Gradually working up to 30 minutes in the sauna daily.
Rehydrate thoroughly and scale back training volume - don’t add it on top of your training, but cut back on your runs. 

However, it is very important to realize that this is also a stressor and counts as something you need to recover from.

No sauna?
Try:

• Hot tub immersion - also a good tool if you don't have access to a sauna, using the same protocol as outlined above.
• Wet sauna (less effective, but useful)
• Running in layers during the hottest part of the day

Megan says: "I’ve heat-trained and not heat-trained for Western States. For several years, I lived near the course, where the climate is generally quite hot 1-2 months before the race. I was prepared by running in the hottest part of the day in the 4-6 weeks in the lead-up.

"However, in 2021 I moved to a colder climate and couldn’t rely on natural adaptation and followed this sauna protocol, outlined above. It worked -   not only did I feel comfortable in the heat but, surprisingly, I felt I handled the altitude better in the first 30 miles of the race over 7,000 feet, due to increased plasma volume".

Add CurraNZ for a Heat Edge

If you want to take things further, research suggests CurraNZ may help you handle heat stress more effectively. A 2024 study found that NZ blackcurrant extract enhanced the heat shock levels in unacclimated runners at baseline. This was potentially reduced heat stress responses and improved runners' tolerance to the heat – so be sure to add the Purple Pill to your heat training regimen in 7-day lead-up to a hot event.

Key Takeaways

• Start heat training at least 10 days before your hot-weather event
• Use passive heat strategies after your usual session warm-up 
• Reduce your training load while heat training
• Include CurraNZ in the race lead-up (2 caps/day) to support your heat tolerance 

Whether you’re lining up for Western States, Badwater135, or any endurance event that will be held in hot conditions, smart preparation - with supporting help from the purple powerhouse – will get you to the start line in good shape to perform in summer races.

References:

Périard JD, Racinais S, Sawka MN. Adaptations and mechanisms of human heat acclimation: Applications for competitive athletes and sports. Scand J Med Sci Sports. 2015 Jun;25 Suppl 1:20-38. doi: 10.1111/sms.12408. PMID: 25943654.

Conrad NJ, Heckler EP, Lee BJ, Hill GW, Flood TR, Wheeler LEV, Costello R, Walker EF, Gillum TL, Willems MET, Kuennen MR. New Zealand blackcurrant extract modulates the heat shock response in men during exercise in hot ambient conditions. Eur J Appl Physiol. 2024 Aug;124(8):2315-2328. doi: 10.1007/s00421-024-05439-w. Epub 2024 Mar 7. PMID: 38448730; PMCID: PMC11322260.