Running in Heat and Humidity

Be careful out there! Remember, when you run in humidity, your body can't properly cool itself down. When the humidity is high, your sweat cannot evaporate and cool your body down, causing the sweat to stay on your skin and your body heat to stay high. This makes running dangerous.

If your body heats up and gets dehydrated, it goes into survival mode, maintaining blood flow to your essential organs and to your skin to regulate temperature. This will cause less blood to flow to your GI tract, which will make the digestion of sports drinks or gels difficult, making you feel nauseous.  You are also more prone to side stitches when you are overheated, because your breathing becomes shallow and uneven causing a lack of oxygen being delivered to your muscles. And your heart rate will escalate as your heart and lungs work overtime trying to deliver oxygen throughout your body. I often notice my heart rate will be shy high on hot and humid days!

If you continue to run, your brain temp will rise, which makes matters worse: Your ability to assess your own body temp will become difficult. You may experience goosebumps when your are overheating.  You can also start to lose control of body mechanics (your form and footing will get sloppy) and your mental abilities may start to break down causing you to feel dizzy or disoriented.

It is important to know that as humidity increases, thermal strain and premature fatigue increases exponentially, and so running at your normal pace will feel very difficult. It is important to recognize that feeling sluggish on a sticky day doesn't indicate a lack of fitness or a lapse in mental toughness, it's your body's physical response to a stressful environment.

Here are some early warning signs of heat exhaustion and heat stroke:  fatigue, nausea, dizziness, headaches, tingly skin, and confusion. Call it quits if you experience any of them, even if you haven't reached the end of your run or the finish line.

How to run smart when heat and humidity rise:

*Hydrate Well
At least four hours before your run drink 16-20 oz. of water and aim to drink 3-5 oz. every 15 minutes. During a race, I try to remember to drink every time I pass a mile marker. You should also drink whenever you feel like you need it.

If running for longer than an hour, add 3-5 oz. of electrolyte water and carbs every 15 minutes. You all know I prefer Hüma Chia Energy Gel and Nuun Hydration when I am training and racing.

*Salt
Salt helps your body retain and distribute water,  so shake some on your meals when humidity is high. Eat a few extra salty snacks.

Information adapted from Runners World


Marathon Performance and Weather Conditions

We don't often take into consideration running conditions and temperatures. Do you realize that the best temp to run a marathon is 55°F? At 75°F you have a degradation of 7% and at 85°F a degradation of 10%.  

Going below 55°F has the same effect. At 35°F, you have a degradation of 7%.

Think about it, your body has to work hard to cool you down core. As your body temp increases your oxygen uptake increases, glycogen depletion is hastened and lactate levels increase. You will notice a rise on your heart rate. It is almost impossible to have a peak performance on a hot race day. Even the elite runners come in slower at a hot marathon.

Take all these things into consideration when racing in heat and don't get mad at yourself for not hitting your PR.

Stay hydrated, run in the shade whenever possible, stay off hot asphalt, and stop if you experience any signs of heat exhaustion: headache, nausea, chills, dizziness, faintness, muscle cramps, strong and rapid pulse, hot and dry skin, confusion.

Info adapted from RRCA