It’s summertime again, and that means running in the heat and humidity. I’ve been putting in summer miles for nearly 30 years now, and I’m still caught off guard when the first couple weeks of oppressive temperatures hit. Along the way though, I’ve picked up some useful tips that can help you conquer the heat and reach your fall racing potential!

Calculate your sweat rate:

Calculating your sweat rate can be a game changer for your summer training as it provides personalized hydration insights essential for optimal performance and health. By knowing your sweat rate, you can prevent dehydration and overhydration, maintain electrolyte balance, and regulate body temperature. This helps enhance endurance, sustain energy levels, and improve recovery.

Steps:

1. Pre-run Preparation:

o Empty your bladder.

o Weigh yourself nude or in minimal clothing. Record this weight (in pounds).

2. Run:

o Run for a fixed period, typically 1 hour. If you plan to measure for a shorter duration, make sure to adjust the calculations accordingly.

o During exercise, keep track of any fluids you consume. Measure the amount in fluid ounces.

3. Post-run:

o After your run, towel off any sweat.

o Weigh yourself again in the same minimal clothing or nude. Record this post-exercise weight.

4. Calculate Sweat Loss:

o Subtract your post-run weight from your pre-run weight. This difference is the weight lost due to sweat.

o Convert this weight loss to fluid ounces (1 pound = 16 ounces).

5. Adjust for Fluid Intake:

o Add the amount of fluid consumed during your run to the weight loss from step 4. This gives the total fluid lost through sweat.

6. Determine Sweat Rate:

o If you ran for 1 hour, your total fluid loss is your sweat rate per hour.

o If you ran for less than or more than 1 hour, divide the total fluid loss by the number of hours to get your sweat rate per hour.

Example Calculation:

1. Pre-run weight: 154 pounds

2. Post-run weight: 153 pounds

3. Weight loss: 154 pounds - 153 pounds = 1 pound (which is 16 ounces of sweat lost)

4. Fluid intake during run: 8 ounces

5. Total fluid loss: 16 ounces (sweat) + 8 ounces (fluid intake) = 24 ounces

6. Run duration: 1 hour

7. Sweat rate: 24 ounces per hour

Tips:

For accuracy, ensure consistent conditions for pre- and post-exercise weighing (e.g., same clothing, empty bladder).
If exercising in varying conditions (e.g., different temperatures or humidity levels), consider calculating your sweat rate under those specific conditions.
Repeating the measurement multiple times and averaging the results can improve accuracy.
Overall, it's important for you to listen to your body and stay hydrated throughout the day, not just during exercise.

Adjust your pace to the Dew Point:

Knowing the dew point helps you gauge the humidity levels and adjust your pace and hydration strategies accordingly. High dew points indicate increased moisture in the air, which hampers the body's ability to cool itself through sweat evaporation, leading to higher risks of overheating and dehydration. By understanding the dew point, you can make informed decisions to maintain your performance and safety, such as slowing your pace, increasing fluid intake, and modifying your running schedule to avoid the hottest parts of the day.

Research suggests pace adjustments based on the dew point:

Dew Point < 55°F: No adjustment

Dew Point 55-60°F: +0 to +30 seconds per mile

Dew Point 60-65°F: +30 to +60 seconds per mile

Dew Point 65-70°F: +60 to +90 seconds per mile

Dew Point 70-75°F: +90 to +120 seconds per mile

Dew Point > 75°F: +120 to +180 seconds per mile

Note:

These adjustments are approximate and can vary based on individual runners' acclimatization and fitness levels.
Runners should use this graph as a guideline and adjust based on their own experience and comfort.
Dew Point can be found on your preferred weather app.

You will acclimate, so don’t give up:

On average, it takes your body about 7 to 14 days to acclimate to the heat. During this period, the body undergoes several physiological adaptations that improve its ability to cope with high temperatures. These adaptations include improved sweat response, better blood flow to the skin, more efficient cooling mechanisms, and an overall increase in plasma volume. Gradually increasing the duration and intensity of runs in the heat can help you acclimate more effectively, ensuring you maintain performance and reduce the risk of heat-related illnesses.

As an added bonus, training in humid conditions boosts your cardiovascular efficiency and overall stamina, making your body more resilient to heat stress. Additionally, the increased challenge of running in humid conditions can improve mental toughness and discipline, which are crucial for peak performance in various climates. As a result, when you compete or train in less humid environments, you may find running easier and more comfortable, giving you a competitive edge.

Run during the coolest part of the day and plan ahead:

This may seem obvious, but early mornings or late evenings typically offer lower temperatures and reduced sun exposure, making it easier for your body to regulate its temperature and maintain optimal performance during your run. Cooler conditions also help preserve energy levels and improve overall comfort during the run, allowing for better quality training sessions. Additionally, running in cooler temperatures reduces the strain on the cardiovascular system, leading to more effective and safer workouts.

Planning your route ahead of time can also be effective. Choose shaded paths or routes with access to water. Consider loops or out-and-back routes where you can refill water or take breaks if needed.

Don’t be afraid of the treadmill:

Running on the treadmill occasionally when it is hot out can be beneficial by providing a controlled environment that reduces the risk of heat-related illnesses and allows for consistent training. Treadmill running helps avoid the extreme temperatures and high humidity that can lead to dehydration, heat exhaustion, and heat stroke. It also allows you to maintain your training schedules without compromising performance or safety.

Additionally, treadmill workouts can be tailored with specific inclines and speeds, offering varied and effective training sessions that can enhance overall fitness. This controlled setting ensures you can continue to build endurance and strength without the added stress of adverse weather conditions.

Last summer, on average, I did 4 of my 11 runs a week on the treadmill. I thought it was a nice change of pace to get out of the heat for a little while. You can also split a run between the treadmill and outside. For example, 20-30 minutes outside, then a quick transition indoors to the treadmill for another 20-30 mins.

If you're interested in personal run coaching, reach out to me via email at marathonandbeyondtraining@gmail.com. Happy training!