Tips for Running in Humid Weather
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Updated August 05, 2015.
Any runner who has slogged through a hot and humid run knows how difficult and potentially dangerous it can be. When the humidity is high, the air can't absorb more water, so your sweat can’t evaporate and produce a cooling effect.
If humidity is an issue where you live, here are some tips for before, during, and after your runs so you can train, but still stay safe and avoid heat-related illnesses.
1. Get acclimatized. If you live in an area where rough winter weather makes it difficult to train outdoors, start running outside as soon as you can. Your body will adjust to the weather as it warms up rather than shocking your system by going from comfortable indoor running to hot, humid weather outdoors. Start off with shorter, slower runs in the humid weather and gradually build up your pace and distance.
2. Run early. Morning is the best time to run to avoid the peak temperatures and humidity levels. Although temperatures may cool in the evening, the roads have still been heating up in the sun all day and will still be radiating heat.
3. Wear a visor, not a hat. Even if you wear a breathable, mesh running hat, you’ll still hold a lot of heat in. Wearing a visor can protect your face and eyes from the sun, but will still allow the heat to dissipate off the top of your head. In addition, the visor’s sweatband will prevent the sweat and sunscreen from dripping into your eyes. If it starts raining, the visor will also keep the rain off your face.
4. Skip the caffeine. Drinking coffee, tea, or other caffeinated beverages before a humid run can cause you to generate more heat, and will also increase your heart rate.
5. Hydrate! When the weather is hot and humid, the easiest way to avoid heat disorders is to keep your body hydrated. This means drinking fluids before, during and after exercise. The current fluid recommendations for runners say that they should "obey your thirst" and drink when their mouth is dry and they feel the need to drink. In training, drink before workouts and make sure you have access to fluids if exercising longer than 30 minutes. During longer workouts, some of your fluid intake should include a sports drink (like Gatorade) to replace lost salt and other minerals (electrolytes).
6. Take breaks. Take walking breaks when the humidity is very high. Going uphill is a good time to take a walk break.
7. Reduce your intensity. Humid days are not the time to do intense speed workouts or super long runs. If the humidity is high, lower your intensity and run at a more moderate pace. Reduce your distance so you avoid temptation to push yourself beyond your limits. If you’re trying to follow a training schedule and have to get a workout in, use a treadmill or indoor track pushing yourself too hard. If you are an athlete in training, consider running on an indoor track or treadmill until the humidity eases and/or your body gets used to it.
8. Sip cool water after running. When you’re done with your run, get inside (or at least in the shade) and sip on cold water to cool your body down.
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