Running Is Hard. And it’s harder when it’s hot, because your core temperature increases and makes you feel a bit worse than normal, as if you were running a fever. And as your body starts to heat up, blood is diverted to the skin, where cooling takes place through sweating and evaporation. Because of this, blood is less available to transport oxygen to muscles. Less oxygen means it is harder to increase or maintain your pace. And as you dehydrate you have a harder time sweating, thereby causing your body temperature to rise faster.
Sounds terrible. What Do I Do?
Slow Down.
It takes time for your body to adjust to hot and humid weather. As the temperatures begin to rise, back off your speed and intensity by 25-30 percent. Then over the next week or so, gradually build back to your regular pace and intensity. Your body should acclimatize, given enough patience and time. Wear a heart rate monitor as well. Your HR automatically increases in the heat, so keep an eye on it as your run and adjust accordingly.
Drink Up.
You have heard it a hundred times. You must hydrate before, during and after your run, especially when it’s very hot. Many runners remember to re-hydrate after a run and some drink during the run, but it's equally important to be well-hydrated before you run. If your run is on the shorter side, drink 16 or so ounces about 2 hours before. If you have a long run or event, start hydrating in the days or weeks leading up to the race.
As a guideline, if you plan on running 45 minutes or less, you shouldn’t have to carry water. If you are running 45 minutes or more, you will definitely want to carry water and/or an electrolyte replacement, such as Nuun. Everyone is different, so you will have to figure out what works for you. Remember, DO NOT wait until you feel thirsty to drink. If you're thirsty, you're already dehydrated.
Get Up.
When possible, run in the early morning, at the coolest part of the day. The hottest part of the day is around 5 p.m. So, if you can't run until after work, wait until it cools down a bit.
No Cotton.
Cotton t-shirts, socks, bras and shorts hold onto sweat and keep it next to your skin, which leads to irritation and blisters. Plus, it’s just uncomfortable. Tech fabrics will keep you cool and wick sweat, which helps prevent chafing. Socks and clothing made from bamboo fibers as well as Smartwool are also effective in moisture management. Another tip: Hang-dry your tech fabric running clothes. The fabric softener in dryer sheets can decrease moisture-wicking abilities.
Uh Oh.
You’re running in heat and you don’t feel so well. If you are feeling symptoms of heat exhaustion such as heavy sweating, paleness, muscle cramps, tiredness, weakness, dizziness, headache, nausea, vomiting, and/or fainting, you should try to cool off immediately. Drink cool non-alcoholic liquids and take a cool shower, bath, or sponge bath. If the symptoms worsen or don’t subside within an hour, seek medical attention. If heat exhaustion is not treated, it may lead to heatstroke, requiring immediate medical attention.
Like heat exhaustion, heat stroke can result from exercise or heavy work in the heat combined with inadequate fluid intake. Heatstroke can be life threatening because the body loses its ability to cool itself. Symptoms of heatstroke include rapid heartbeat, rapid and shallow breathing, elevated or lowered blood pressure, lack of sweating, irritability, confusion or unconsciousness, dizziness, headache, nausea, and/or fainting. If you feel like you or someone you know might have heatstroke, call 9-1-1.
Be a Pal.
It’s always nicer to run with a friend, and in extreme conditions, it’s also safer. One of you should have a phone with you, and remember not to run too far from your home or your car. Do a few loops instead of a long out and back, just in case.
Just because it’s hot, doesn’t mean you have to go inside to run, just be smart, slow down and drink up.
This article was compiled from a variety of on-line running sources as well as staff experience.