The purpose of this study was to investigate the effect of rapid weight reduction for short duration
on serum enzyme and stress hormone in high school wrestlers. Subjects were composed of 7 student wrestlers whose wrestling careers were 3years over. Subjects were reduced 5% of their body weight by exercise, reducing food and sauna method for three days. On the basis of the results analyzed in this study and consideration of many pre studies related it, the result could be drawn as follows. First, Data analysis of 5% weight reduction on CPK, post level revealed more significant increase than pre level(p<.05). Second, Data analysis of 5% weight reduction on LDH, post level revealed more significant increase than pre level(p<.05). Data analysis of 5% weight reduction on Epinephrine, post level revealed more significant decrease than pre level(p<.05). Data analysis of 5% weight reduction on Norepinephrine, post level revealed more significant increase than pre level(p<.05). In conclusion, rapid weight reduction gives an effects on decreasing wrestlers' physical fitness suddenly during the match because of changing rapidly of serum enzyme and stress hormone in the body. I hope that more studies will be followed on serum enzyme and stress hormone in rapid weight reduction of weight class competition players in the future.