Humidity Big Factor in Summer Running

Today, around noon, I ran my convoluted course around my home neighborhood, totaling exactly nine miles. In 90 degree weather, with the humidity hovering around 60%. I perspired a lot, but took some safety measures: I walked for about a minute every seven minutes, chugging down a little refrigerated Powerade Zero during each walking period (I finished the 20-ounce bottle by the run's end, the last drops by then being warm). After the run, I downed another cold bottle of Powerade Zero and stepped into a cold shower for several minutes, these steps helping to cool both the exterior and interior of my body. Then, I downed a large cold protein shake to further aid in my recovery.

All of those measures notwithstanding, had the humidity been, say, 10-15 % higher, I would have probably had to cut my run short of 9 miles. For once the temperature reaches a certain threshold, it is the humidity that plays a dramatically important role in my training.

In the summertime here in northern Florida, the evening temperature (without thunderstorms) usually is around the 80 degree mark, more or less. That in itself can be quite uncomfortable to run any appreciable distance in, but what's worse is that the humidity here tends to skyrocket after sunset, sometimes reaching 85-90%. I have seen many runners wait for the nighttime and they look as if they are about to have a heatstroke in the humidity and darkness!

In order to be able to properly perspire, the air has to be dry enough to bring out the sweat. High humidity has an effect of blocking perspiration, which can contribute to the body's overheating and health dangers. So I would much rather run in hotter temperatures with a relatively low humidity. Which is why I never did take to night running.

That being said, I'm not sure my loved ones know what to make of me running nine miles in 90 degree weather with the sun beating down on me!