Heat acclimation: Five tips for riding in the heat

Summer temperatures can throw a curve-ball into your training. Intervals that once felt easy now seem out of reach. The hot temperatures are not only uncomfortable, but they begin to wreak havoc on your abilities and your recovery. Will the heat ever be easier to tolerate? How can you work to maximize performance even in sub-maximal conditions?

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What Happens During Heat Acclimation

The first few days in the heat will be the hardest, but it will get better. Heat acclimation generally occurs in 9-14 days of consistent heat exposure.¹ A more highly-trained athlete will likely make adaptations faster than a less-trained athlete.

Over the course of that two-week adaptation period, your body is working to make positive physical changes to support your new, and hotter environment. A few noteworthy changes are that you will sweat more and earlier in your workout to help cool your body more efficiently. You will experience a more even distribution of sweat across your body, and your sweat will become more dilute in order to preserve sodium.¹
 
While these changes are happening automatically in your body, here are some conscious changes to your routine that you can do to help support your body’s heat acclimation process.

Five Tips for Riding in the Heat

1. Consistent and gradual exposure: In order to adapt to heat as quickly and as efficiently as possible, you must maintain consistent exposure. A hot ride followed by several days off or in cooler environments will not promote heat adaptations. Additionally, heat acclimation that is not maintained will be lost within 3 weeks from a lack of exposure.
    
   When you decide to — or are forced to — adapt to heat, it is important to gradually increase your workout intensity and duration. Be patient with yourself as you try to hit your intervals and do not become frustrated with yourself if you are not seeing your usual numbers. The National Collegiate Athletic Association proposes that practices should be kept to three hours or less during the first five days of heat exposure.²
2. Hydration strategies: There is no one-size-fits-all approach when it comes to fluid and electrolyte replacement during exercise. Due to varying temperature conditions and personal factors, not only will each individual have different requirements, but each ride for an individual might require different strategies.
    
   A great way to monitor your hydration levels is by weighing yourself before and after a hot ride. If your body mass is decreasing by two percent or more throughout the ride then you may have experienced a decrease in performance due to a lack of hydration. The goal is to keep your body mass within two percent of starting weight throughout a hot ride. Should you fail to do so, you should re-hydrate to the point of being back within that two percent before the next ride.³ It’s important to remember that the proper fluid replacement will contain electrolytes such as sodium and potassium.
    
   If you know that you will struggle to carry enough fluids during your ride then consider doing a loop that will take you back by your house, car, or other water sources in order to refill your bottles throughout the ride.
3. Ice slushy drinks: A great way to help reduce your body temperature while riding is through an ice slushy drink. This adaptation of the favorite drink utilizes crushed or blended ice, water, and/or a sports beverage. A slushy drink has been shown to be superior to just cold water or ice water. Consuming a slushy drink before or during a ride has been proven to have positive physiological benefits for an athlete exercising in hot conditions.
4. Pre-cooling: It’s very important to keep your body cool before beginning exercise. Something as simple as spending time in air-conditioning before your workout may help your performance. More advanced forms of pre-cooling may be cool-water immersion, or utilizing an ice vest. While those strategies might not be realistic for an everyday ride, the concept can still be applied. Try wetting down your hair, put some ice in your jersey, or a cold washcloth around your neck before starting your next hot workout.
5. Recovery: When exposing your body to extremely hot conditions for exercise, recovery can become even more important. Along with adequate rehydration, you should focus on cooling down your body. The ice bath is a popular way to not only decrease body temperature, but also to limit inflammation.

Stay Cool

Heat can be an intimidating and frustrating element to battle during the summer months. As you try to maintain your cool, remember that that is exactly what your body is attempting to do as well. Stay mentally strong and assist your body in acclimating to the rising temperatures. Next thing you know your speed with be rising again as well.
 
References

1. Kenney, W. Larry., et al. Physiology of Sport and Exercise. Human Kinetics, 2015.
2. Casa, Douglas J., et al. “National Athletic Trainers’ Association Position Statement: Exertional Heat Illnesses.” Journal of Athletic Training, 2015, doi:10.4085/1062-6050-50-9-07.
3. Mcdermott, Brendon P., et al. “National Athletic Trainers’ Association Position Statement: Fluid Replacement for the Physically Active.” Journal of Athletic Training, vol. 52, no. 9, 2017, pp. 877–895., doi:10.4085/1062-6050-52.9.02.