Abstract:

Background: Various exercise tools are used in abundance during training and rehabilitation of athletes susceptible to shoulder injury as a means to strengthen stabilizing muscles of the shoulder, and trunk. In contrast to the vast amount of literature evaluating muscular activity during traditional medicine balls and Bodyblade® tools, there is no peer reviewed literature evaluating muscular activity during exercise using new varieties of medicine balls that are currently being sold to rehabilitation and exercise professionals. Hypothesis/
Purpose: The purpose of this study was to compare the electromyogram (EMG) activity of shoulder and trunk stabilizing muscles during three commonly performed medicine ball exercises using both a standard medicine ball and a ballistic medicine ball (SB)
Methods: Twenty-four healthy volunteers (17 female and 7 male) with a mean (± standard deviation) age of 35.5±9.2 years and a body mass index (BMI) of 22.7±2.8 were enrolled. Following a familiarization session, wireless surface EMG probes were placed on subject’s infraspinatus (IS), latissimus dorsi (LD), anterior deltoid (AD) and external obliquus (EO). The order of exercises and ball selection were randomly drawn. Each subject performed three exercises using MB and SB.
Results: There were no significant (p >0.05) differences in maximal and mean muscle activity in any muscle group between exercises with the MB and SB. Two-way analyses of variance showed no significant (p< 0.05) differences in muscle activity between the two ball types for all muscle groups.
Conclusions: This study suggests that the new SB exercise tool may be a useful tool for rehabilitation of athletes in need of tools to aid in shoulder and trunk stabilization. The lack of statistical significance between ball types suggests there is no added benefit to use the SB over traditional MB. Future study is recommended using a variety of SB and MB weights and sizes to further evaluate muscle recruitment during common exercises using these tools. Practical Application: Rehabilitation therapists and exercise professionals alike may further consider utilizing newly marketed exercise tools not as a replacement of traditional tools, but rather as a compliment for training variety in athletes.