I was on local ESPN radio a couple of weeks ago (22 June) with my friend and trainer Chris Leben, discussing the medical implications of rapid weight loss — intentional dehydration — to reach a specific weight goal by a specific time. http://www.unfilteredmma.com/shows.htm
Although this is not a popular topic among the general public, it does dovetail with the science of nutrition and athletic performance in the sense that following a restricted carbohydrate diet, as I reference about halfway through the video, reduces the body’s free water retention at all times and therefore probably takes some of the pressure off the athlete in terms of shedding that water to achieve a weigh-in goal.
Not only that, but multiple endurance records are being set by the use of a restricted carbohydrate diet, including the US record of the longest distance run in a 24 hour period (172 miles, by Mike Morton, a Special Forces soldier). Carb-loading is just about dead.
Although cutting weight is very dangerous if not done properly, I can definitely attest to the benefits of fighting at a higher weight than one’s opponent. Being on the ground with Chris Leben (who outweighs me by about 40 pounds), is an extremely tiring experience. For example, once he has side control with a “thoracic wedge” in place to increase the pressure even further than his body weight, it almost impossible to breathe which obviously has implications for having the strength to have an effective ground game. Of course, fighting skill can overcome these challenges to some extent.
Generally, starting from a well-hydrated state, most well-conditioned athletes can safely lose about 5% of their weight by a controlled, slow dehydration, and this should be done under competent medical supervision. No, a lawyer didn’t tell me to say that… Also, Christina Marks won her fight.