Exercising In the Heat

Exercising in the heat does not pose the same physiological challenge as exercising in the cold. A vital concern during exercise is heat loss, which decreases with high temperatures and humidity. If your body is unable to lose heat, body core temperature starts to rise and you are at risk for heat illness, which can be life-threatening. Guidelines for exercise in the heat are the following:

1. Avoid strenuous exercise when the temperature is high (above 90 degrees Fahrenheit), especially if the relative humidity is also high (greater than 60 percent).
2. Wear light, absorbent clothing.
3. Cover your head to decrease absorption of radiant heat.
4. Exercise early in the morning or late in the evening, when the radiant temperature is not as high.
5. Decrease intensity of exercise and monitor yourself for signs and symptoms of heat-related problems.

(ACSM, Heat and cold, 1998; Hoeger and Hoeger 2002)

Arthritis problems related to exercising in the heat are different than those encountered in the cold. They are more likely to occur if you have a systemic type of arthritis, such as rheumatoid arthritis, or other systemic disease. In such cases your heat loss mechanisms may not function as well, meaning you may be more susceptible to heat-related illness. It is true that heat may reduce stiffness, but other systems (such as your cardiovascular system) may not adjust as well. Following sensible guidelines becomes even more important, and you should consider alternative exercise routines.