Does The Heat Slow Us Down, or Do WE Slow Ourselves Down?

OK, we know that its been drilled into your head time and time again: Drink to so that you can sweat, sweating cools you and makes your body perform better. Simply correlation, right?

Except that some have weighed in with the theory that heat doesn't diminish our athletic performance at all, it is our brain's expectation that the heat will cause problems with out bodies that makes us slow down and be more cautious.

Novel, you might say, if you're the sort that thinks about these sorts of things. Except, no matter how simple or outlandish the theory, there will be scientists somewhere who will try to challenge conventional wisdom.

And an interesting study was published in the European Journal of Applied Physiology, conducted at the University of Bedfordshire and University of Brighton, with cyclists as lab monkeys. They had seven riders riding a time trial under three different heat conditions:

1. a control trial @ 21.8 centigrade
2. a hot trial @ 31.4 C
3. and a "faux" trial @ 31.6 C with false indicators that the room was at 26.0 C

So what happened? The cyclists covered less distance on the hot trial than the control trial, which was expected, but performed just as well, even a little bit better, in the "faux" trial when conventional wisdom says that they shouldn't have performed as well!

Now this obviously brings up the discussion of why runners typically slow down in heat, is it because we THINK we're going to over heat, and the body's protective mechanism is to lessen our effort so that we don't get into core heat trouble. Ross Tucker, part of Tim Noakes' group in South Africa (Noake's Lore of Running book in an indispensible work BTW), argues that exactly that: we slow down so we don't get into trouble IN THE FUTURE, not at what our body is at currently.

So what do we make of this in regards to, say, running a Double Dipsea? One, that the longer we're exercising the higher our core temp will go, that's an unchallenged given, so a testing duration of 30 minutes is very different than one of 2 hours, 4 times as much. Part of our brain telling us to be careful may be dictated by our knowledge of just how long, or how short, we'll be out there. Obviously extreme core temp changes can be dangerous long term, but it certainly appears that we can trick our bodies into moving less blood to the surface of the skin for a period of time. And in a close race, that may be all the difference you need.

We have seen Kenyan runners, especially the late Sammy Wanjiru, in the heat of Beijing, run performances that are so utterly beyond what we think is possible that it is tempting to put the onus not on Sammy being a world class athlete, which he was, but on having a brain that simply refused to acknowledge that the heat would slow him down. Because what we saw was Sammy run the race in a time that, while fast, is not beyond what he had already run at London. What is interesting is that Sammy ran AS IF he was at London in cool temps, while the REST OF THE WORLD CLASS MARATHONERS ran as if they ran in the heat.

So can the average runner benefit? It might be interesting to have coached "lie" a bit to athletes, to see what happens. It would not be the first time. And if its not a marathon, perhaps what you don't know won't hurt you.