Why I Died

A couple of weeks ago I somewhat foolishly ran the Queens half marathon in sweltering temperatures. As I was recovering from the race I received the following email:

Oh my gosh did you really run the Queen’s Half today? You are my hero. I am working in the ER today (thankfully not one in Queens) and we were all saying how happy we were not to be working in one of the Queen’s ERs. I have worked in some of the medical tents during marathons, halves and triathlons and all I can say is WOW…healthy people can get sick fast.

This email was from a star Foodtrainee who is training for the NYC marathon. We’ll call her Dr O (or in this case maybe I should say Dr Oh No!). It was opportune to hear from Dr O as I happened to have a few questions for her. Not only had I crashed and burned in Queens but I also observed countless fellow runners “losing their Gatorade” and lying down on the sidelines in what yogi’s aptly call corpse pose. I emailed Dr O some of my questions:

In hot weather what do you see in the medical tents, it sounds like MASH?
We see hyperthermia, heat stroke, dehydration, hyponatremia and general orthopedic injuries like pulled muscles, stress fractures etc.

Why was Queens so miserable? I trained well, felt good, hydrated appropriately what is it about the heat that killed me?
I think the Queen's 1/2 was so miserable for many reasons. One, it was in Queens (I did that run a few years ago and it is not pretty). It was so hot that your core body temp had to have been very high which makes the muscles and heart demand more fuel and oxygen, also it was humid...humidity is dangerous. One way for the body to cool itself is by sweating and then having that sweat evaporate. When the air is already saturated with water (high humidity) the sweat does not evaporate....and you don’t cool ! With no way for your body to cool your internal temperature rises. Throughout the race your core temperature was rising which is why, despite fuel, things felt harder as the race went on. If you want to keep up a certain pace, either the blood (and oxygen) goes to your muscles to keep up with the pace demands and you start to overheat because less blood is going to the skin for cooling or the blood goes to the skin for cooling, but less blood goes to your working muscles. Either way demands exceed supply. When we have a hyperthermic patient we cover them in ice and put fans on them (well we did before we got a $250,000 hypothermia machine). No machine at the half marathon though.

What does your GI system take a toll when running in the heat?
Dehydration seems to exacerbate GI symptoms and that may be why it’s worse in hot weather. Also, blood is redistributed during extreme exercise and there is some ischemia to the diaphragm. At rest 15-20% of the blood goes to skeletal muscle but during exercise this increases to 80-85%. The jolting of running stresses the ligaments that support the abdominal wall. You see more GI issues in running than in cycling. Vomiting can be a sign of hyponatremia, which though extremely dangerous is still fairly rare and usually involves hydrating 2-6 liters beyond what is suggested.

Thanks Dr O. I now understand what was happening. I’m still slightly flummoxed (and jealous if I’m honest) that some people seemed to be unaffected by the heat. They ran well and finished respectably. Maybe it’s A/C. In my obsessive research I read to truly acclimate to hot weather one shouldn’t spend the majority of their time in A/C….too bad that’s not going to change!
Do you have any medical questions for Dr O about eating or exercise? Do you prefer extreme hot or extreme cold (seems people pretty split)?