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Monday, January 7, 2008

Dehydrated States and an Increase Performance

There was an interesting study conducted at an English marathon in 1967 on the dehydration levels of the race participants (Pugh et al. 1967). The findings suggested that the top finishers in the race were more dehydrated than the rest of the field. There was a mean weight loss of 6% for the top finishers of the race. How could this be, that race winners were the most dehydrated? The result of this study was a complete contradiction to the findings of leading study in dehydration, Adolph (1946).

Scientist believed that dehydration was a negative contribution to race performance, and that dehydrated states caused participants to stop activity. This was not the case for the winners of the English marathon. Instead of the linearity between the increased dehydrated states and the decline in performance, the Pugh et al study linked high performance levels with a increase in dehydration (Armstrong 190).

One principle that might have been overlooked is the tolerance of dehydration amongst elite athletes. It is true that the winners of the English marathon in 1967 had the most fluid loss and the highest rectal temperatures compared to the rest of the field. This could possibly just illustrate that the top finishers were well adapted to dehydrated states and high body temperatures. Acclimitization to heat and water loss is a key factor to building a "resitance" to dehydrated states. Yes, it is also believed that humans can't adapt to dehydration, that the body has no built in mechanism that overrides this physiological stress. Both arguements are rightly justified.

There is also a possibility that in longer endurance races such as the marathon that athletes can perform better being somewhat dehydrated. The top finishers in the English marathon lost 6% of their body weight. So let’s say that the winner of the race weighed 120 lbs before the competition and after weighed 112.8 lbs. That is a 6% weight reduction. This means that being dehydrated allowed the winner of the race to finish with 7.2 less pounds of weight.

A 6% change in body weight can tremendously affect race performance. For example, pretend two competitors were of the exact fitness and weight, and that if these two competitors raced they would tie. Now distribute 7.2 lbs of water weight throughout one of the runners. There would be a dramatic difference in the result of the two identical runners racing. The winner between the two would be the one who didn’t have the 7.2 lbs of water weight, and this is why it can be said that being dehydrated can benefit a runner due to the lighter body weight (Armstrong 190).

-Sean Bowman-

2 comments:

Justin Kunz said...

Very interesting points Sean, Thanks

Anonymous said...

Interesting article Sean.