The effects of chronic dehydration using bioelectrical impedance on isokinetic strength and endurance in college wrestlers.

Abstract

The objective of this study was to determine what changes in body water occurred in wrestlers from preseason to season's end and whether these changes effected muscle strength and endurance of the dominant quadricep. A bioelectrical impedance analyzer (BIA) yielded actual body water measurements as the means of determining dehydration.

Nineteen subjects (age = 18.9 yr) participated in a pretest, followed by two post tests {dollar}4{lcub}1\over2{rcub}{dollar} months later. Data were collected for physical characteristics, quadricep strength and endurance, and perceived exertion.

The wrestlers in this study lost an average of 2.88 pounds prior to the start of the season to the first testing session (Post Test A/Chronic Dehydration). The average amount of water loss measured by the BIA was 0.05 liters.

A multivariant analysis of variance (MANOVA) revealed a significant difference (p {dollar}>{dollar}.05) between tests measuring changes in body water. Tukey's test indicated a significant difference did not exist between the preseason and Post Test A. This post-hoc test showed the significant differences were between the pretest and Post Test B and between Post Tests A and B (Acute Dehydration). These results indicated the wrestlers' body water levels remained relatively constant throughout the season, except just prior to making weight.

A MANOVA showed that no significant difference existed in muscle strength and endurance of the quadriceps between any of the independent variables. These findings are in agreement with 62 percent of the studies reviewed pertaining to dehydration and muscle strength and endurance.

As total body water decreased, wrestlers' rating of perceived exertion increased. No significant difference between tests comparing perceived exertion and changes in body water was found. Further research may show if wrestlers are not losing strength through dehydration, they may be mentally less ready to compete in the later minutes of their match due to lower levels of body water.