The Journal of Orthopedics Research and Rehabilitation welcomes scholarly papers inorthopaedic surgery, physical therapy and rehabilitation, neurosurgery, neurology and clinic anesthesiology and reanimation.

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Original Article
Hamstring muscle activation during the flywheel exercises
Aims: Aim of this study was to determine hamstring activation during flywheel (FW) exercises, identify differences between muscles and classify the exercises.
Methods: Exercises were done by professional footballers and electromyography data from hamstring muscles were recorded and normalized according to maximum voluntary isometric contractions (MVIC). Differences between muscles and with-in exercises were compared with repeated measures ANOVA and categorized according to their intensity.
Results: The Exercise variable had significant differences (F(3.1,81.5)=96.5, p<0.05) but the muscles variable F(1,26)=2.24, p>0.05) and Exercise*Muscle interaction effect (F(3.1,81.5)=0.97, p>0.05) were not a significantly different. During Romanian Dead Lift, Single Leg Dead Lift, Leg Curl and Single Leg Hamstring Bridge determined over 80% activation according to MVIC for biceps femoris (BF) and medial hamstring (MH) with not significantly different between each other and they were categorized as high-intensity FW exercises (p>.05). During Bilateral Squat for both musclewere determined below 50% according to MVIC and it was categorized as low-intensity FW exercise. During Single Leg Squat and LUNGE in the MH were below 50% according to MVIC, these exercises were categorized as low-intensity FW exercises and in the BF in the range of 50-80% according to MVIC so they were categorized as medium-intensity FW exercises.
Conclusion: With this study, both parts of the hamstring contract similarly during the selected FW exercises. Low or moderate intensity FW exercises can be used in the early stages of rehabilitation or preventive hamstring exercise programs, while high intensity ones can be used in later processes.

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Volume 1, Issue 4, 2023
Page : 75-80