Dehydration Does Not Necessarily Lead to Heat Stroke

This runner more than likely is suffering from dehydration- not heat stroke. Note it's raining and spectators are wearing jackets- it's cold.

Intensity of Exercise Increases Body Temperature- Not Dehydration!

You shouldn’t relate overheating to dehydration. You overheat when you run too fast. That’s the key. You don’t overheat because you become dehydrated. The brain’s too clever. If you’re not going to drink, the brain will slow you down, and that will lower your body temperature, not raise it. So, we’ve got some great studies where we look at people running half marathons, marathons, short ultramarathons, and long ultramarathons. The longer the race, the lower the temperature, because they are running slower - Tim Noakes in Outside Online.

MY COMMENT:  Noakes is stirring up a hornets nest.  I didn't realize 4 of the 6 researchers who published the ACSM Guidelines on Dehydration had ties to Gatorade.  According to Noakes,  "Of the six authors, four – Drs. Maughan, Burke, Eichner and Stachenfeld – have direct and longstanding involvement with Gatorade and the Gatorade Sports Science Institute (GSSI), but only three (Drs Maughan, Eichner and Stachenfeld) deemed it necessary to disclose in the Position Stand the existence of that relationship. The two remaining authors – Drs. Sawka and Montain – are employed by the United States Army Research Institute for Environmental Medicine (USARIEM)"  -sweatscience

Waterlogged! Everything You Think You Know About Dehydration But Don't!

"If fluid loss leads to thirst, why do some of the best competitors finish endurance races in quite advanced states of fluid loss? Time and again, studies, even those by researchers expecting different outcomes, have shown that the runners who are the most dehydrated, as measured by percentage of body weight loss, run the fastest. " - Waterlogged excerpt in Running Times MY COMMENT: Tim Noakes is generally recognized as the leading authority on dehydration and endurance performance. I can't wait to read this new book!

Caffeine Does NOT Dehydrate!

To test dehydration, 59 physically fit males were given 246 mg of caffeine per day for six days. After the six-day equilibrium period, the men were split into three groups and embarked upon a five-day test period. The first group was given double the amount (492 mg) of caffeine per day, the second group acted as the control group and kept receiving the same 246 mg per day, while the third group's caffeine intake was dropped to zero.

RESULTS: Results showed no sign of a negative fluid-electrolyte imbalance in any of the test groups

dailycampus.com

MY COMMENT: As the article states, "the key to caffeine consumption is moderation"

Rehydrate With Food!

...five male and three female cyclists cycled in a steamy environment (34 degrees Centigrade, 55 per cent humidity) until they had dehydrated them-selves by about 2 per cent of body weight. After the exercise, the athletes ingested either a carbo-hydrate-electrolyte sports drink or else a standard meal comprised of 53 per cent carbohydrate, 28 percent fat, and 19 percent protein, along with water (at a volume 1.5-times greater than the amount actually lost during exercise).

Total urine output was significantly lower after the meal, compared with the sports drink, probably because of all the electrolytes (especially sodium and potassium) naturally found in the food, which helped hold water in the body. When only the sports drink was ingested, the subjects' body-water levels were still down by about 10 to 11 ounces six hours after the exercise had concluded, while the meal-and-water combination restored fluid balance to normal ('Restoration of Fluid Balance after Exercise-Induced Dehydration: Effects of Food and Fluid Intake,' European Journal of Applied Physiology, vol. 73, pp. 317-325, 1996). Obviously, combining good water intakes with consumption of electrolyte-rich foods can be a great way to rehydrate. -pponline.uk

MY COMMENT: Eating after a long workout does much more than restock muscle glycogen!

Racing and Ibuprofen

Those runners who’d popped over-the-counter ibuprofen pills before and during the race displayed significantly more inflammation and other markers of high immune system response afterward than the runners who hadn’t taken anti-inflammatories. The ibuprofen users also showed signs of mild kidney impairment and, both before and after the race, of low-level endotoxemia, a condition in which bacteria leak from the colon into the bloodstream. -nytimes

MY COMMENT: Clearly ibuprofen intake prior to and during marathons and ultras poses some serious health risks and no benefit in terms of reducing inflammation or pain (this study looked at Western States 100 competitors).

Some general rules on taking ibuprofen are:

1. Do not take ibuprofen before, during, or shortly after lengthy endurance exercise, especially when there is potential for dehydration.

2. Take ibuprofen with a full glass of water or milk, ideally with meals to avoid stomach irritation.

3. Do not combine ibuprofen with alcohol.

4. Do not take in combination with other medicines, supplements, or herbal products without first consulting with your physician or pharmacist.

5. Avoid if you have a history of any reaction or allergy from another anti-inflammatory medication.

6. Discontinue use immediately if you notice any of the following symptoms: urine that is cloudy or bloody, pain or burning in the stomach, diarrhea or black tarry stools, severe nausea, indigestion or heartburn, vomiting blood.

7. Do not use if you are pregnant or breast-feeding.

8. Talk to your doctor first if you have high blood pressure, liver or kidney disease, heart failure, ulcers or other stomach problems.

-Iburpofen- Friend of Foe (article I wrote a few years ago)