18 Apr 2011 Summer fitness prep 101
by Karl Lenser
The heat and humidity will soon be upon us, and for those who like to exercise in the great outdoors, special precautions need to be taken. The main areas of concern are hydration and acclimatization.
During exercise, we create a tremendous amount of heat, which must be dissipated in order to regulate our internal temperature. During the cool months of fall and winter, the heat is easily eliminated because the heat easily evaporates into the atmosphere. However, when the heat and especially the humidity valves are unleashed in the summer months, our bodies begin to struggle with maintaining a safe internal body temperature. High levels of humidity create a very difficult scenario for the evaporation process and often can lead to a variety of heat-related problems.
The best ways to stave off these potential adverse problems are to hydrate with an ample amount of fluid and exercise in the early morning or later in the evening. I am amazed when I see individuals jogging outside in sauna-like temperatures during the noon hour. People who exercise vigorously in hot and humid conditions can lose up to a half a gallon of fluids per hour. If these fluids are not replaced, then dehydration can occur.
So, how do you know when you are hydrated or dehydrated? The best way is to check the color of your urine. Clear (almost colorless) urine means you are hydrated adequately, while a pale, darker yellow color indicates it is time to reload on fluids – preferably water or a sports drink.
Another good tactic that aids in the battle against the heat and humidity is to get acclimated. People who are fit and in good shape will be able to better adapt to the heat as compared to poorly conditioned folks. Usually it takes about two weeks to become acclimated to the heat and humidity, but it may take longer for some individuals. Gradual exposure to the tropical weather that we experience in our Arkansas summers is the best plan of attack. Hydrate, acclimate and try to exercise in the early part of the day or in the later evening.
Meteorological Tidbit: When the dew point hits 70 degrees or higher, the conditions outside become tropical and very sticky. When I go out for a run in the mornings during the summer, I always take a look at the dew point temperature. I find it interesting that a 73 dew point compared to a reading of 70 is quite significant. A reading of 75 and higher is just plain brutal – even at 5:30 a.m.
Generally speaking, when the air temperature is at least 80 degrees and the humidity is at least 45 percent, conditions become less and less safe for exercise. The more these numbers climb, the worse the conditions will become.
Make sure you plan ahead when you head outside for a walk, run or yard work. Bring fluids and pack the sunscreen! More on this to come in another article.
