"Extreme Heat Slowing You Down? It’s All in Your Head" Erik Malinowski, WIRED 5.20.2011

It’s one of the basic principles of human physiology, that when extreme heat sends your core temperature off the charts, your body slows down. Maybe it’s regular ol’ fatigue, or it could be the lactic acid building up in your muscle tissue, but at least it’ssomething tangible.

Or is it?

A joint study conducted by researchers at two British universities has opened up the possibility that when coaches yell at athletes to just “play through the pain,” it’s way more conceivable than we thought.

The study, recently published in the European Journal of Applied Physiology, involved seven male cyclists engaging in various 30-minute stationary trials. Subjects were allowed to ride their own bikes, thanks to the use of a KingCycle ergometer, but what the study ultimately hinged on was that the temperature of the environment was displayed for the cyclists.

The control trial was conducted in a room kept at 71.2 degrees Fahrenheit. A second “hot” trial was held in a room at 88.5 degrees. The final one was a “deception” trial, in which the temperature was displayed as 78.8 degrees but it was actually 88.8 degrees, the hottest of the three. The trials were administered in a randomized way, and all seven subjects performed all three. (Rectal thermometers used to measure each cyclist’s core body temperature were also displayed as being slightly lower than what they were actually were.)

What researchers found was that while cyclists performed better in the control trial (10.33 miles) than the hot trial (9.87), they actually traveled a greater distance on average in the deception trial (10.4) than the other two. And the mean power output — the wattage pumped up by all that exertion and cycling — was actually higher in the deception trial (184.4 watts) as opposed to the hot trial (168.1). There was no discernible output difference between control and deception, even though one was conducted in a setting 17 degrees hotter than the other.

It’ll be fascinating to see where the research goes from here, but it’s noteworthy that exercise output, even in difficult conditions, can be so directly impacted solely on visual cues like the readout on a temperature gauge. The results could have a significant effect on any sport or activity that combines intense physical exertion with high temperatures. (Aside from competitive cycling, soccer and marathon-running are the two most obvious candidates.)

And with all sorts of training gadgets that can help you keep track of heat both internal and external, it sure would be great if you could hack one to knock the temperature down a few clicks.

_____

"Extreme Heat Slowing You Down? It’s All in Your Head" Erik Malinowski, WIRED 5.20.2011