Isokinetic Characteristics of Knee Flexors and Extensors in Male Dancers,Olympic Oarsmen,Olympic Bobsleighers,and Non-Athletes

Abstract

Quadriceps (PT_QUAD) and hamstring (PT_HAM) concentric peak torques — measured in Nm and Nm·kg^-1 body weight — and hamstring/quadriceps peak torque ratios (PT_HAM/QUAD) were studied in males engaged in different physical activities and having different levels of physical fitness. Both dominant and non-dominant legs of 20 professional dancers, 14 Olympic oarsmen, 11 Olympic bobsleighers, and 10 non-athletes were isokinetically assessed at 1.04, 3.14, and 4.19 rad·sec^-1. The main findings were: 1. torque levels decreased with increasing angular velocity in all four groups of subjects; 2. with few exceptions, dancers and non-athletes demonstrated significantly lower PT_QUAD and PT_HAM (p < 0.01 to p < 0.005) at the three velocities than bobsleighers and rowers; 3. most of the differences between groups described above, disappeared (p > 0.05) when PT_QUAD and PT_HAM were standardized for body weight (Nm·kg^-1); and 4. although PT_HAM/QUAD for dancers and non-athletes were significantly lower than that of the two sports groups at 1.04 and 3.14 rad·sec^-1, no such differences were noted at the relatively higher velocity of 4.19 rad·sec^-1. We conclude that dissimilar physical training, modes of exercise, and/or different fitness levels have the same effect on muscle contractile characteristics.