Summer’s Almost Here: Time To Start Acclimating

Welcome to the wonderful world of summer running here in Central Texas. We had a wet, cool winter and spring, but I can guarantee will have another extremely warm summer. Hopefully, not the record-breaking kind we endured a few years ago, but it will be disgustingly hot nonetheless.

Great.

Running through a hot, steamy summer is never easy—especially if you’re training for a fall marathon, replete with plenty of long runs–but it can be done safely and effectively.

The problem with running in the summer is quite simple. It’s the oppressive heat (duh) which makes it so much more difficult to run because our bodies have to work much harder on hot, humid days than on dryer, cooler days to get rid of all the heat we generate on a run.

That’s a physiological fact, but our bodies adapt surprisingly well to the heat. It’s called heat acclimatization and the key is allowing the body to gradually adapt to the unique stresses that heat places on us when running.

Heat acclimatization is a wonderful thing to talk about, but the only actual way the body adapts to the heat, is to train in the heat. There is no other way.

Exercise scientists say it takes approximately two weeks of warm-weather running for the body to adapt and make the necessary physiological changes. So you still have a little time before the blast-furnace days of summer arrive next month.

As your body adapts during this two-week period, running becomes easier as the body begins to cool itself more effectively. The most important changes that take place are to the heart which pumps more blood with each stroke. With more blood being pumped near the surface of the skin, you’ll be able to get rid of more heat through your skin.

As more blood is pumped to the skin surface, you’ll sweat more. Contrary to popular belief, sweating is a good thing because sweat is the body’s best way of cooling itself through evaporation.

Sweating is the key to keeping your body temperature at a safe level in warm or hot weather. But as we Central Texans know all too well, not all warm weather is the same.

The main difference is humidity. On a dry, but hot day, more than 80 percent of your body heat is dissipated by the evaporation of sweat from your skin. But on an extremely humid day (such as we’ve already seen this May), the sweat from your skin evaporates slower and is much less effective at cooling the body. That’s why running on a dry, but hot day may feel easier than on a more humid, but cooler day.

Still, after about a week of running in warm weather, you should start to feel a bit more comfortable in the heat. But not everyone adapts to it in the same way. Some runners sweat a lot (which is good), but too much sweating sets them up for being more prone to becoming dehydrated which is not good.

Acclimating to the heat won’t have much of an effect on dehydration. The body can get used to running in the heat, but not to a loss of fluids. So one of the keys to acclimating to the Texas heat is to increase your fluid intake before, during and after running.

We all know we should drink plenty to keep you properly hydrated, but even copious amounts of fluids won’t keep you cooler or lower your body temp. Still, quite obviously, drinking adequate amounts of fluid is important.

The key to acclimating to the heat is to do so gradually. Slowly increase the length and intensity of your runs in the heat, but only in short doses. Your first few runs in the heat should be very easy, short and stress-free. Going for a long, hard run won’t speed up your adaptation to the heat.

Here are some warm-weather running tips to keep in mind:

1. Drink before, during and after every run. Drink at least 12-16 ounces of water or sports drink before you run to make certain you’re fully hydrated. It’s critically important that you begin a warm-weather run already dehydrated.
2. Before running, check the temperature and humidity to make sure it’s not excessively brutal. If it is over 85 degrees with a relative humidity of 75 percent or higher, go for a shorter run than planned. If it’s above 90-95 degrees and the humidity is over 85 percent, either run indoors on a treadmill, go for a walk, bike ride or a swim.
3. Check your weight every morning. If your weight has dropped significantly in the past day or two, you’re probably dehydrated. If so, drink enough water, juice or sports drink to bring it back up. (Water weighs 2 ½ pounds per quart.)
4. Check your weight after every long, hot summer. Here in the ATX, it is not uncommon to lose 8-10 pounds after a long summer run. If that’s the case, pound the fluids immediately afterward.
5. In your first few warm-weather runs, go easy. Don’t push the pace, length or intensity of the runs.
6. Never wear heavy clothes (such as a jacket, sweatshirt or tights) in warm weather. This is a common mistaken belief that this will help you adapt more quickly to warm weather (or lose weight). It doesn’t work and is extremely dangerous.
7. Wear as little as possible. The less clothes you wear while running, means less heat will be trapped close to the body. Wearing less, also means the sweat can evaporate better and cool you off.
8. Recognize warning signs of heat exhaustion: Headache, chills, tingling sensation on arms or back, pale, moist skin, rubbery legs, red skin and rapid pulse. If these symptoms are present and you feel weak, stop running immediately and get to a shaded, cool area. Better yet, get inside an air conditioned building or dunk yourself in a pool.
9. Don’t eat excessive amounts of salt. It won’t help.

10. Avoid alcohol immediately before and after running. If you want a post-run beer, make sure you drink at least 20 ounces of water or sports drink first.
11. Avoid running during the hottest time of the day. Earlier is usually better than later—even if the humidity is higher.
12. If possible, try to run on a shaded dirt trail or grassy field. Both are cooler surfaces than a road.

Wish

About Wish

Bob “Wish” Wischnia has more than 30 years of running industry experience across publishing, retail, web, and race organization. An Arizona State University alum, Wischnia has been a runner virtually his entire life, still competing in track and road race competitions. And in the free time he’s not pounding the pavement? He’s swimming, cycling, and catching days on the green.