Date of Award


Document Type

Scholarly Project

Degree Name

Master of Physical Therapy (MPT)


Physical Therapy

First Advisor

Thomas Mohr


Electromyography; Muscles -- physiology


Many training programs have been developed to aid in training the athlete with their goal of maximizing strength and performance. The Plyo Press machine was developed for training athletes enrolled in the Frappier Sports Acceleration Program. This machine was designed to couple strength training with plyometrics to enhance dynamic muscle activity and speed.

There has been limited research on the Plyo Press machine to support these claims. Therefore, the purpose of our study was to compare muscle recruitment during a vertical floor jump versus a plyojump in the Ply Press leg machine. EMG analysis of selected lower extremity muscles was conducted to provide information of the muscle activity and recruitment pattern evoked during exercises on the Plyo Press.

Eight healthy male subjects that were familiar with the Plyo Press machine were asked to participate in this study. Each subject performed a series of vertical jumps and then plyojumps on the Plyo Press. An analysis of the normalized EMG data was conducted using the Norquest software package. The results of this study revealed that there was significantly more muscle recruitment of the gluteus maximus, semitendinosus, and anterior tibialis during the vertical jump as compared to the Plyo Press. The Plyo Press does not appear to offer any advantage of increased muscle recruitment for athletic training.