Adding Cold Inside and Out to Manage Heat During Exercise

Last week I blogged here about my upcoming family vacation trip to Arizona and Nevada with my sister and her three kids. This week has marked a serious heat wave there—and trust me, when they say “heat wave” in the southwest, they’re not playing. It was 116F/47C on Tuesday in Phoenix, AZ. A mountain biker, five hikers, and at least one other person have died in the past 5 days as a result of the extreme heat.  Local authorities have tried a variety of ways to try to convince people (locals and visitors) that it’s not safe to hike in such hot weather.  Signs like these are an obvious choice, and signage designed to convey messages to non-English speakers are also in progress.

The weather outlook for next week in northern Arizona and Las Vegas looks slightly cooler; by this I mean highs ranging from the low 90s at the Grand Canyon to 110 in Vegas.  Some very nice blog readers from AZ alerted me and offered tips on places to go and how to deal with the heat– thanks, readers, y’all are wonderful!

I will certainly heed everyone’s advice.  We will:

NOT hike except in early morning (good luck to me on getting folks out of bed..);

Go to some of the famed Arizona swimming holes that the internet told me about here;

Cool off at unfamed but sufficient-unto-the-day swimming pools at our various motels;

Do more scenic drives like this and this, with stops for nature walks and photo ops.

Surely, though, science and technology have something more to offer us in the way of keeping cool(er) in the heat.  As usual, the New York Times was very accommodating in covering recent studies on keeping one’s body temperature cooler.  Here are three ideas.

1. Drink sugary slushies before exercise.

Here’s a quote from the NYT article:

…young male recreational athletes who drank a syrup-flavored ice slurry just before running on a treadmill in hot room could keep going for an average of 50 minutes before they had to stop. When they drank only syrup-flavored cold water, they could run for an average of 40 minutes.

The article goes on to say that this test was for endurance, not performance, and it has other limitations, among them the lack of knowledge about the underlying mechanisms involved in the interactions between cooling and athletic performance.

I must add that every study I found used 20-something male athletes as participants.  There are loads of reasons to think they are not at all a representative sample of the athlete population, the population of those who exercise, or the population of those who get hot in the summer.  Just saying.

Okay, that’s fine.  I just need to get three kids through a few national parks.  If it takes a few of these, so be it.

2. Apply cool/cold directly to your body– preferably your neck, head, or torso.

There have been various studies on the use of cooling neck collars suggesting they increase the amount of time people can tolerate hot-weather exercise.  One potential problem is that they don’t actually keep the body temperature down, but rather dampen the conscious response to the heat.  Also, they need to be frigid in order to be effective.  I’m not sure that sounds like a good plan for my sister’s children (or my sister and me, for that matter.)  Still, there are loads of such vests and neck wraps available online.

3. Cool your underwear.

There’s another NYT article with the great title,“Slushies vs. Frozen Underwear for Hot-Weather Workouts”.  In it, the study is described below, comparing performance on 3 different 30-minute runs in hot temperatures (in a lab) for 12 male experienced runners:

Before one of these runs, the men sat quietly in the heated lab for 20 minutes, sipping a room temperature, sweetened beverage.

Twenty minutes before another of the runs, they drank about 16 ounces of a sweetened slushy drink, which quickly and significantly lowered their core temperatures.

Finally, 20 minutes before a third run, the volunteers elaborately lowered their skin temperatures by draping cold, wet towels around their neck, sticking one arm into cold water, donning a frozen cooling vest, and slipping on underwear equipped with frozen ice packs at the thighs. Not surprisingly, their skin temperature fell considerably.

I wonder if they used these to cool their underwear– a product called Snowballs (I’m not kidding):

According to the researchers, the effects of icing the skin lasted longer than the internal cooling provided by the slushies.  But none of the effects lasted very long.

Probably my low-tech, common-sense strategies (aided by reader advice) will stand us in good stead in the week to come.  I am insisting on us doing a bike tour of the south rim of the Grand Canyon, so I guess I’m buying the slushies.  Does anyone know if they come in non-nasty flavors?  I hope I’m not going to be stuck ordering from the menu below.