Friday, July 13, 2012

Do not let the heat stop you - Running in the heat

There was this wonderful article that I was reading online on RunningWorld.com, just in time for our next half-marathon, MOO-nlight half tomorrow in Davis. It starts at 7pm when the temperatures would be in upper 80s. To make it worse, Shavi is going to run it without having fully recovered from his back spasm, that happened a few weeks ago. Since he wouldnt read this good long article, I thought to copy the important points from the article and paste them here for him.

Here it goes:

Running in sauna-like conditions can throw your internal equilibrium seriously out of whack. The body normally cools itself by moving blood—which is mostly water—to sweat glands in the skin, says Douglas Casa, Ph.D., A.T.C., COO of the University of Connecticut's Korey Stringer Institute. The glands create sweat droplets that carry heat to the surface of the skin, where it evaporates.

Once your body temperature climbs to 104 degrees, you're in the heatstroke danger zone. Continued hard running at this temperature can overwhelm your cardiovascular system. Hit 105 degrees for 30 minutes or more and your body may start to cook from the inside out. The hyperthermia can weaken the heart, cause the kidneys and the liver to shut down, and cause cell damage. Exertional heatstroke has arrived.

Three things as per researchers could optimize performance while running in heat:
1. Acclimatization, getting your body used to exercising in the heat;
2. Proper hydration, which stocks blood-plasma stores and replaces fluid lost through sweat;
3. Pre-cooling, which involves deliberately lowering core body temperature within 30 to 60 minutes of the starting gun.

For morning race:
1. Eat salty food with dinner. Sodium not only makes you thirsty (so you drink more), it helps your body retain fluid—and the final 24 hours before a race is a critical period to hydrate.
2. Drink 600 milliliters (about 20 ounces) of water three hours before bed. Check for light-colored urine. If it was darker than the color of straw, my instructions were to drink an additional 300 milliliters, or 10 ounces. (Drinking to the point of colorless urine can cause hyponatremia, a condition where blood-sodium levels dip to life-threatening low levels.)
3. Morning day race: Drink 300 milliliters to top off your tank. Eat more salt, like an extra-salt bagel.
4. Pre-cooling is the process of deliberately lowering core-body temperature 30 to 60 minutes before exercising in the hea, maybe Drink a Slurpee one hour prior to start.
In 2010, researchers from New Zealand found that runners who drank an icy, sweet drink ran 10 minutes longer on a treadmill in a heated room than runners who drank syrup-flavored cold water. The "ice slurries" lowered their core temps, which may have allowed them to run longer before their bodies overheated. In short, they were better pre-cooled.
5. For runs of an hour or less, drop your pace by 30 seconds per mile. For runs over an hour, scale back by 60 seconds.

The best thing about heat illness is that it's preventable. "You simply have to pay attention to how your body feels," says Douglas Casa, Ph.D., A.T.C. "If things feel strange, back off." Here's what happens if you push it too far—and how to bring yourself back.

HEAT CRAMPS: Painful muscle contractions that occur during or after intense exercise
The Cause: Muscle fatigue, water and sodium loss
The Symptoms: Dehydration, cramps, fatigue
The Treatment: Massage, rehydrate

HEAT EXHAUSTION: Inability to continue exercise due to overwhelmed cardiovascular system, depleted energy
The Cause: Exercising in hot or humid environments, dehydration
The Symptoms: Include fatigue, irritability, nausea
The Treatment: Move to shade, elevate legs, apply ice bags, rehydrate

HEAT SYNCOPE: Fainting episode that occurs in high temps, typically during initial days of heat exposure
The Cause: Coming to a standstill immediately after activity, or standing suddenly or for long periods causes blood to pool in legs
The Symptoms: Dizziness, tunnel vision, pale skin, weakness, decreased pulse rate
The Treatment: Move to shaded area, elevate legs, rehydrate

EXERTIONAL HEATSTROKE: Potentially fatal condition characterized by a core temp of 105° F
The Cause: Includes vigorous exercise in a hot environment for more than one hour, poor fitness
The Symptoms: Include hyperventilation, disorientation, dizziness, vomiting
The Treatment: Full immersion for 30 minutes in cold (35 to 59° F) water

Reference article, can be found at: RunnersWorld