Effect of body position on hamstring muscle group average torque.

The purpose of this investigation was to examine the effect of the supine and prone position on concentric and eccentric isokinetic strength of the hamstring muscle group. Twelve university female lacrosse players were tested for hamstring average torque on a Kinetic Communicator(R) dynamometer at 60 degrees /sec from the supine and prone positions. Analysis of variance indicated average torque generated from the prone was greater than the supine position. Greater torque was also generated during eccentric contraction than during concentric contraction. The influence of the tonic labyrinthine and the symmetrical tonic neck reflexes is proposed as the mechanism for the differences observed between the two test positions. The prone position facilitates optimal generation of torque while approximating a length-tension relationship observed during sprinting. These findings suggest consideration be given to assessment and strength training of the hamstring muscle group in the prone position. J Orthop Sports Phys Ther 1990;11(10):449-452.