Articles : Changes of Blood Electrolytes and Body Composition after Rapid Weight Loss Through Dehydration and Caloric Restriction

Journal of Exercise Nutrition & Biochemistry 2003;7(1):55-62.

Abstract

Taekwondo players perform at the lowest weight class possible in order to gain a competitive advantage. The major technique of rapid weight loss was using a combination of the dehydration, fasting, and increased exercise in taekwondo players. This study examined the changes of body composition and blood electrolytes after rapid weight loss of about 55 through dehydration and caloric restriction of 3 days. Subjects were 24 college-aged male taekwondo players, and divided to two groups as rapid weight lass group (n=12 : WL) and control group (n=12 : CO). WL group performed the rapid weight loss program of 3 days through sauna (30min/day) and caloric restriction (18㎉/㎏/day). Body weight significantly (p<0.05) decreased after rapid weight loss in Wl group, but percent body fat showed no significant difference. In WL group, abdominal skinfold thickness, waist circumference, and thigh circumference significantly (p<0.05) decreased after rapid weight loss as compared to before weight loss. Blood K+ concentration significantly (p<0.05) decreased after rapid weight loss in WL group. From these results, the rapid weight loss through dehydration and caloric restriction of 3 days showed no significant change in body composition, but reduced a preferential reduction in abdominal fat. And 5% rapid reduction in body mass would have no effect on blood fluid change, but it could be suggested the imbalance of blood electrolytes after rapid weight loss.

Key Words: rapid weight loss, dehydration, body composition, electrolyte