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Climate: How It Affects Your Physiology

The weather can influence your body in various ways that will often leave you feeling perplexed. You might be wondering why your times are slower, you feel sluggish, or have an elevated heart rate. So let’s look at some of the key meteorological factors:

 

 

A sufficient enough headwind will physically counter your forward motion, raising your heart rate. A good tailwind will have the opposite effect—you’ll go faster at the same heart rate.Temperature may also be a factor during your test. High heat and low cold will raise your heart rate, forcing you to slow down.High humidity can act much like a headwind. It is a physical barrier of water that you must work through. The increased effort raises your heart rate and results in a slower test.Rain and snow are similar to humidity and headwinds. Going through rain (and to a lesser extent snow) requires more effort. In addition, if the surface you are on is wet with water or, especially, covered with snow, additional physical effort is required (much of this is the brain being overcautious as you bike, for example, with increased tension in your muscles while riding in case of a fall).Barometric pressure can also have a slowing effect on your MAF Test. Low barometric pressure results in a slightly lower oxygen uptake. The result is less oxygen getting to your muscles and your body compensates by raising the heart rate.

Often, weather stress is not the result of a single factor. A combination of cold and wind, for example, can elevate the heart rate significantly. Summer heat, humidity, and low pressure, sometimes referred to as the “dog days of August,” can also stress your body and raise the heart rate. The dew point is also an important factor. Relative humidity is a measure of how humid it is; the dew point temperature measures how much water vapor is in the air. High dew points that approach 75°F are most noticeable when training or competing outdoors—the air feels thick with moisture because the water vapor is very high. For these reasons, if you arrive at your MAF Test day and the weather is extreme, wait a day or more until the weather stress has lessened.

Altitude can have a significant effect on the body and MAF Test, especially if you have not had a chance to adapt to a new altitude. If you’re headed for the mountains to train for a period of time, wait at least a week or more until you adjust to the altitude before performing your MAF Test. Even then, your times generally slow when you ascend to higher altitudes. When descending to lower altitudes after adapting to high altitudes, your MAF Test usually improves.

These weather factors not only affect your MAF Test, but all training, racing, and, in fact, virtually all human performance, including chemical function, such as hormone balance, and mental activity, such as scholastic testtaking. The end result of much of this weather stress is human error; there are more accidents associated with certain weather changes, for example, including low barometric weather systems affecting the body.