FITNESS CLUB

As the season changes, the body adapts to the environment. Being aware of your body's response to the changing conditions helps you to continue enjoying life without compromising your safety. The temperature is milder now for instance and some of my regular readers have been wondering how to cope with the change.

The main environmental factors that impact our exercise routine are extreme temperatures, humidity, altitude and air pollution. Of all these environmental factors, heat is potentially the most hazardous. Concerted effort should be made to prevent your body temperature from increasing excessively and to prevent dehydration while exercising.

Acclimatise to the heat

Your ability to manage heat can be achieved by gradually acclimatising yourselves when exercising in a hot environment. This approach not only makes you more tolerant of increases in body temperature, but to increases in heart rates at specific exercise intensities. If you perspire under these conditions, your rate of perspiration will be complementary to the intensity of the exercise routine.

You acclimatise yourself by exercising for short periods, about 10 to 15 minutes in the first session, and gradually increase the time at each session. Healthy individuals will take a week and a half to two weeks to become acclimatised to the heat and they will need to maintain tolerance by exercising regularly under similar conditions. Routinely, as little as two days without exposure to the heat will incur a day's loss of acclimatisation.

Tolerate the cold

By contrast, your body tolerates exercising in lower temperatures much better. Temperatures as low as minus 31 degrees Fahrenheit or minus 35 degrees centigrade can be tolerated by healthy people without undue distress. It will not impair your body's ability to provide the requisite oxygen or energy supply for energy production. Thus, the discomfort being experienced by some of you especially in central Jamaica and the hills of upper St Andrews (where it can get relatively cold at this time of the year) need not prevent you from exercising outdoors.

If your core temperature is maintained close to normal and you are appropriately attired in layers of clothing to keep your body surface comparatively warm, the opportunity to exercise would not be compromised. Essentially, you should dress to minimise the sensation of cold.

However, sometimes this actually reduces your potential for heat loss and symptoms of overheating and dehydration are induced. The amount of clothing needed to maintain core temperature will decrease as the intensity of exercise increases. Dressing in a number of layers of clothing will facilitate the removal of layers when you begin to feel too warm and uncomfortable.

If you are inappropriately dressed, your core temperature will deviate from the norm and your exercise performance could be adversely affected because of heat loss. Your body would then need to compensate by producing more energy to regain the heat and energy lost which will require you to exercise more vigorously.

Dr Kenneth Gardner is an exercise physiologist at Holiday Hills Research Center; email: yourhealth@gleanerjm.com.