With the heat wave sweeping most parts of the country right now, it's an opportune time to talk about its effects on athletes. Yes, it's tough, very tough. And it does slow your pace by 1.5 to 3 percent for every 10-degree jump above 55 degrees. However, believe it or not, studies show many positive correlation effects of heat on athletic performance.
First, it helps increase the body's rate of perspiration. In other words, when you sweat more, it helps your body stay cool by lowering your core temperature. In the bodybuilding community, a measure of fitness is often assessed by asking, "yo bro, how much do you bench?" However, in the endurance community a better question is, "yo bro, how much do you sweat?" Fit people sweat more because their bodies are better at increasing perspiration! So remember that the next time you're drenched on the commute to work.
Second, training in the heat increases the body's blood plasma volume. This is the liquid component in your blood. When the volume is increased, you increase the supply of oxygen to your muscles. Also, more blood flows to vital organs. This allows you to work at a higher rate for a given level of perceived exertion.
On a more general level, there's no doubt that training in the heat is tough. As your body learns how to work out at a more intense level, "normal" conditions feel much easier. It strengthens your mental muscles, too, as you look back on these training workouts and draw on them when it comes time to race day.
Get out there and workout in this heat! Just remember to hydrate and take in extra electrolytes. When you get back, cool off with some Fly Feet.