This Saturday, I’ll be joining over 400 other runners (and 70 horses) at the Vermont 100 Endurance Race. As 100s go, it’s not the worst: about 17,000 feet of vertical gain and mostly-runnable dirt roads and horse trails. But the wildcard in this race is always the weather. The forecast for race day is stifling high of 97 degrees and a low at night of 70. Also, some thunderstorms! It’s possible that we will be fighting off heat stroke in the afternoon and hypothermia at night. Good times.
At hot races like this, you’ll hear some runners talking about adjusting their strategy by running harder in the cooler morning hours to put some miles “in the bank.” There is a certain logic to this that makes sense: Why not get a bunch of miles out of the way early and then go real slowly during the heat of the day? But there is a better way.
As much as possible, stick to your original plan (if you don’t have one, make one). Running hard early means you’ll be fatigued earlier. You’ll probably be pretty spent at the worst possible time of day, when the temperature is at its highest. Keep in mind that it will cool down later in the evening and that might be a better time to push the effort, especially because you’ll be so much closer to the finish.
Keep yourself hydrated, of course, but don’t overdo it. Drink when you feel thirsty. You’ll probably be thirsty quite often, so it’s fine if your consumption is way up. But trying to over-hydrate or “top off” before the start of the race can actually lead to serious problems. It’s rather uncommon for runners to die of heat stroke in an ultra. More of them have been sidelined and worse by hyponatremia, a condition in which excess fluid in the blood reduces your sodium to dangerous levels. More on that in another post.
Your perception of heat is also important. There is evidence to suggest that if you can keep your head cool (literally) you will perceive your internal temperature to be lower than it actually is. Whenever possible, get your head wet by pouring water over it or putting some ice under your cap. If you’re wearing vest, consider putting ice where the bladder pouch would be. The ice will melt and cool your back. Lay down in a stream if you get the chance.
Plan to change your socks and possibly your shorts and shirt at least once during the race, maybe as the heat breaks and it begins to cool off. If it will get significantly cooler in the night, you do not want to be running in wet clothes. Have a thin wool shirt (like Smartwool) and a light rain jacket if it looks like rain. A thin windbreaker would suffice if it’s going to be dry.
It’s possible to finish these races in high temperatures. Just don’t get freaked out by the heat. Listen to your body and back off if the effort feels too much, especially at the hottest part of the day.
I’m sure I’ll have some more insights after I (hopefully) finish this Sunday!