getting used to the heat and walking for one’s brain

My wife is still sleeping and so I got to check my blogs. I love hotel internet service!

Workout notes Nothing yet; I might stretch when the wife gets up.

I’ve thought about my marathon performance and how I “went south” so badly this time. I did find this article on heat acclimatization.

Heat syncope (e.g., fainting) occurs most commonly during the first 3-5 days of heat exposure. This illness is related to the shunting of blood through dilated cutaneous vessels, postural pooling of blood, diminished venous return to the heart, reduction of cardiac output, and cerebral ischemia. Heat syncope typically occurs when the ambient temperature or humidity rises suddenly, or when a non-acclimatized individual performs exercise in a hot environment. Heat acclimatization reduces the incidence of heat syncope to nearly zero, after 3-5 days of exercise-heat exposure. This period corresponds with cardiovascular stabilization, early in the course of heat acclimatization (see above). Heat syncope is a syndrome distinct from heat exhaustion, because water and salt depletion do not always contribute to heat syncope.

Heat exhaustion is the most commonly diagnosed form of heat illness among athletes, despite the fact that its symptoms are often vague and differ greatly from one situation to another. Clinical descriptions include various combinations of headache, dizziness, fatigue, hyperirritability, tachycardia, hyperventilation, diarrhea, piloerection, hypotension, nausea, vomiting, syncope, heat cramps, as well as “heat sensations” in the head and upper torso. This explains why heat exhaustion is defined as the inability to continue exercise in a hot environment, and involves a diagnosis of exclusion. Heat acclimatization significantly reduces the signs and symptoms of heat exhaustion, after eight days of strenuous, intermittent running.

They present a table which talks about which factors improve with what kind of training. I found the following: early, early in the race, I noticed that the people that I caught were just dripping with sweat; just drenched. On the other hand, I was lightly moist; I simply wasn’t sweating very much. In fact, I had to stop to urinate several times in the first 10 miles!

One of the factors in being heat trained is to be able to sweat at a lower core temperature.

Also, when I did finally grind to a halt at mile 23, I was able to get going again after icing myself down.

So, the long and short is that I need to take advantage of my time in Texas to get out there and sweat a bit. Also, I am bringing an ice chest to my next race (24 hour race in June in Minnesota).

About the marathon: I noticed that the results are up. There were two people who finished behind me; I lost 3 places during my pit stop. The median time for men (runners) was 4:42; for women it was 4:51. There were 79 finishers. The year before, these times were 4:15 and 3:52 (small number of fast women) respectively.

My half way time was 2:36; in short it me as long to do the last 8 miles as it did for me to do the first 13.

Walking: I noticed that Harry Truman was a faithful walker; he walked steadily at 120 paces per minute for most of his adult life.

Image from the Truman Library.

Well, maybe this is one reason he remained sharp. It turns out that regular exercise is good for your brain.

Behind all the good-natured joking about “senior moments” lies real frustration and fear. How empowering, then, that we can do something to ward off normal, age-related memory loss: exercise. No, it’s not as easy as popping a pill. But as Sue Halpern reports in “Can’t Remember What I Forgot,” even a few brisk walks per week can have a measurable effect. Exercise promotes the birth of new neurons in the very part of the hippocampus (a brain structure crucial to forming new memories) that begins to malfunction with age. Exercise also counters age-related shrinking of the prefrontal cortex, an area involved in concentration and working memory (as in remembering a phone number long enough to dial). [...]

Halpern explains, is that solid, peer-reviewed science has not yet proved that anything else works: not herbal supplements, fish oil, vitamin E, almonds, $400 interactive computer software or even crossword puzzles.

Source for the blog article.

No, I am not making rationalizations for my own behavior; by “exercise” they don’t mean the sort of brain baking training that I do.