The purpose of this study was to compare the muscle recruitment of an agonist and antagonist muscle during the step up physical therapy exercise with and without visual electromyographic (EMG) biofeedback. 15 healthy, college-aged subjects were recruited to participate in the study. Subjects performed the step up with and without visual feedback in two separate sessions over a four week period. Muscle activity was recorded from the Vastus Medialis (VMO) of the target leg and Medial Gastrocnemius on the contralateral leg. EMG recordings were collected using a BTS FREEEMG system and data was processed using BTS SEMGanalyzer software (BTS Bioengineering, Brooklyn, NY). Results: Average Gastrocnemius muscle activity during visual sessions was .340 mV (SD .141) and .310 mV (SD .138) during non-visual sessions. Average VMO muscle activity was .309 mV (SD .097) during visual sessions and .299 mV (SD .139) during non-visual sessions. A paired t-test was used to determine statistical significance between visual and non-visual sessions. Values were considered significant with a p<.05. No significant difference was observed between visual and non-visual trials for the agonist and antagonist muscles. Two subsequent trials were conducted while visual, verbal and palpation feedback was given throughout the entirety of the exercise. The results showed greater muscle activity in the agonist muscle and less activity in the antagonist muscle when the subject received biofeedback. These findings support the conclusions of previous studies (Holermann, Taian, Vieira, Taskiran, Ekblom, One-Bin), suggesting that EMG biofeedback can be used as a tool for proper muscle recruitment during physical therapy exercises.
Johnson, Madeline L.; Cooklin, Rachel C.; Faria, Erika N.; Schavo, Taylor M.; and Sternlicht, Eric, "The Use of EMG as a Physical Therapy Learning Aid" (2017). Student Scholar Symposium Abstracts and Posters. 229.