Does dehydration lead to a loss of skeletal muscle mass in ultra-endurance performance?
One problem in our study is the fact that we measured the athletes every day immediately after arriving at the finish line and could not determine correctly whether they were dehydrated or not. In all methods to determine body composition it has to be considered that physical exercise and its effects on the body might influence measuring values, resulting in systematic errors of measurement. As it takes some time for the body to compensate for the dehydration, the timing of measuring body mass after the race might also be of importance. Like dehydration, it takes some time for the body to compensate for the physical race effects. It must be hypothesized that the weight loss during an Ironman triathlon is mainly due to dehydration. Endurance performance leads to dehydration, which results in a weight loss (Walsh et al., 1994). It is stated, though, that the weight loss in an Ironman triathlon derives most likely from sources other than fluid losses (Speedy et al., 2001). Many indices of
