Background and Study Aim: The wrestling events included in the Olympic Games have different weight classes. Most wrestlers reduce their body weight a few days before competition so they can enter the right weight category. Often they use irrational nutritional strategies to make the weight, sometimes even drastically reducing their water intake. The purpose of this study was the knowledge about influence of pre-competition level of hydration on muscle contractile properties in elite wrestlers.

Material and Methods: Sixty three wrestlers participated in the study (27 female and 36 male). We sampled data from the weigh-in for an international competition, recording each athlete's hydration level using bioelectrical impedance analysis and using tensiomyography to analyze the contractile properties of the vastus medialis (VM), vastus lateralis (VL), rectus femoris and biceps femoris (BF) muscles of both legs. Among wrestlers 16 were classified as “less-hydrated” (total body water <60%) and 47 were classified as “more-hydrated” (total body water ≥60%).

Results: Less-hydrated wrestlers of both sexes had a greater (p<0.05) contraction time for all muscles and lower (p<0.05) maximal radial displacement of muscle belly for VL, VM and BF than those who were more-hydrated. Normalize response speed was significantly higher (p<0.05) in more-hydrated athletes of both sexes for both sides of VM and VL and for right side of BF.

Conclusion: Wrestlers who were less-hydrated at the weigh-in had poorer muscle contractile properties, due mainly to the additional contraction time and the lower radial muscular displacement. Years of reducing body weight by wrestlers based on irrational nutritional strategies may have negative effects on health in the future. Therefore, regular monitoring of the health of the wrestlers at the end of their sporting career is essential to develop recommendations for practice of training