Faculty Sponsor

Kelly Helm


Arts and Sciences



Presentation Type

Poster Presentation

Symposium Date

Spring 2020


This study examined the impact of a collegiate soccer practice on freshman female’s gastrocnemius activation while performing a power jump, as measured by surface EMG. The muscles analyzed included the right and left medial and lateral gastrocnemius’. The null hypothesis stated that no significant difference in gastrocnemius activation will exist during post-practice compared to pre-practice testing. Subjects included six, freshman, female collegiate soccer players. Using a Delsys Trigno® Wireless sEMG system, electrodes were placed on the bellies of the gastrocnemius muscles. Participants completed three countermovement box jumps, with a 20-second rest between trials. Muscle signals were processed and sent to EMGworks® Analysis Software for assessment. The root mean square (RMS) of each MVIC was calculated and the greatest MVIC across all three scores was used for normalization. The box jumps were normalized to the greatest MVIC across all three jumps for each muscle analyzed and the maximum amplitude from each jump was expressed as a percentage of the MVIC. The means of the scores for each muscle were used to run a paired two samples mean t-test. The t-test indicated no significant differences in muscle activity from pre to post-practice box-jumps. Therefore, the null hypothesis was accepted. A recommendation for this study would be to assess the difficulty of the 90-minute practice as well as possibly assess different muscles for comparison.

Biographical Information about Author(s)

Ali Quillen is a senior Exercise Science major with a minor in human biology. She will be pursuing a doctoral degree in Physical Therapy after graduation. Her experience as a member of the Valparaiso women's soccer team and passion for exercise physiology are what sparked her interest for this research topic.