Isokinetic characteristics of knee flexors and extensors in male dancers, olympic oarsmen, olympic bobsleighers, and non-athletes

Abstract

Quadriceps (PTQUAD) and hamstring (PTHAM) concentric peak torques — measured in Nm and Nm·kg-1 body weight — and hamstring/quadriceps peak torque ratios (PTHAM/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 PTQUAD and PTHAM (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 PTQUAD and PTHAM were standardized for body weight (Nm·kg-1); and 4. although PTHAM/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.