Health Topics for Sports Medicine

Department of Orthopaedic Surgery

UI Family Care

Temperature And Humidity Effects On Exercise

Exercising in hot and humid or cold and wet weather conditions is challenging and potentially hazardous. By being prepared, outdoor exercise can be enjoyable and safe during any season.

Here are some tips for exercising in heat and humidity:

• Drink plenty of fluids. Dehydration caused by excessive sweating can lead to heat exhaustion and heat stroke. Drink fluids before, during, and after exercise even if you do not feel thirsty.

• Dress for the heat. Wear loose-fitting, light-colored, and lightweight clothes. Cotton is best when sweat-soaked because it has a cooling effect.

• Use common sense. As a rule, the higher the air temperature, the lower the humidity must be to avoid risk of heat injury. For example, when air temperature exceeds 80 degrees Fahrenheit, you are at risk if the humidity exceeds 50 percent. During very hot and humid spells, exercise in the cool indoors or go swimming.

• Take time to adjust. The body needs time to acclimatize to hot weather. It takes 7 to 14 days to fully acclimatize, so gradually increase your exercise time.

Tips for exercising when it's cold and wet:

• Dress in multiple layers of clothing. The outer layer should protect the exerciser from wind, rain, or snow. Cold temperatures, dampness, and wind increase the risk of hypothermia. Sweat cools the body quickly during cold weather and wind evaporates it faster. Wear fabrics that insulate and wick moisture away. Fabrics made of wool and polypropylene are good. Cotton retains moisture and is not recommended for cold and wet weather.

• Protect special body parts like your head, face, hands, and feet. Mittens are better than gloves. Cover the head with a wool cap. Shield the face with a scarf or high collar. Wear socks that retain heat and wick moisture away.

• Drink plenty of fluids. Do not drink alcohol before or during a workout. It makes the body lose heat faster.

• Warm-up indoors before exercising outdoors. Warming your muscles will help prevent injury.

• Exercise with a partner. Let others know where you are exercising.

• Take high sugar snack foods for long workouts.

• Cancel your outdoor exercise or seek shelter if the weather conditions are too severe or you are too tired. Exercising on ice or over snow-covered terrain can lead to falling or injury.

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