Running is a high-intensity exercise and can be physically exhausting even on the best of days. When you add heat and humidity, your run becomes more challenging and less enjoyable. If you train outside regularly and live in area where humidity is a concern, you need to prepare properly before, during and after your run to avoid heat-induced illness and continue your workouts.
Weather usually changes gradually, occasional odd weather patterns excepted. Start running outside as soon as possible if you live in an area that has severe winters. Let your body become used to the weather as it warms instead of shocking it by going from an air-conditioned indoor environment to a hot, humid outdoor environment. Acclimatization over time is better for your health and your running, Dr. Stephen M. Pribut writes on his University of California-Berkeley website. You can also try running earlier in the morning before the heat and humidity reach their high for the day.
Frequency, Intensity and Duration
If you are training for a running event, your schedule is usually set to ensure that you are prepared on race day. If you run for fitness, you control the frequency, intensity and duration of your workouts. On a day when the humidity is high, lower your intensity and run at a more moderate pace; consider shortening the distance of your workout to avoid 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.
A lot of people wait to drink until their workout is done. This is very dangerous if you are going to be running in humid weather. The key is to prevent dehydration and avoid heat-induced illness as well as diminished performance. Drink before your workout to get ready for your run. During your run, drink about 8 oz. every 15 to 20 minutes, dietitian Nancy Clark recommends. After your workout is finished, drink more than you think you need to rehydrate. If you sweat a lot or your workouts last 60 or more minutes, consider adding a sports drink during and after your run to replace lost electrolytes and carbohydrates.
Choose apparel appropriate for the conditions. In humid weather, you need to wear apparel that is light and allows your skin to breathe so that you can sweat and cool your body. Choose run-specific clothing has a wicking property that lifts the sweat away from your skin. Avoid clothing like cotton t-shirts, which do not breathe well and become heavy when drenched with sweat.
If at any time you feel lightheaded or overly hot when running, stop and walk home. Overheating can lead to serious side effects.