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Ishida H1, Suehiro T1, Watanabe S1
1Kawasaki University of Medical Welfare, Department of Rehabilitation, Kurashiki, Japan
Background: Neck pain is one of the most prevalent musculoskeletal conditions. Multimodal interventions including manual mobilization techniques plus exercise (e.g., strengthening, endurance, flexibility, postural, coordination, aerobic, and functional exercises) are recommended for treating people with acute neck pain with movement coordination impairments. The activities of the limb and trunk muscles during the use of oscillating devices held in 1 or 2 hands was previously analyzed, and the devices have been used for rotator cuff muscle strengthening and trunk stabilizing exercise. Based on the requirement of motion for adept use of the oscillating device, it may be designed to challenge the user's muscles with regard to coordination, rapid recruitment or decruitment, endurance, and strengthening. Therefore, using an oscillating device by holding it in the mouth might be a type of coordination exercise for the cervical muscles. To achieve up-down oscillation of an oscillating device held in the mouth in horizontal orientation, swings would be cervical flexion-extension or knee flexion-extension in a standing position.
Purpose: This study aimed to quantify the activities of the cervical muscles while using an oscillating blade held in the mouth with different swings.
Methods: Ten healthy male university students participated in this study (20.8 ± 0.9 years). The activities of the sternocleidomastoid and C4 cervical extensor muscles were measured using electromyography (EMG) for 5s while using an oscillating blade held in the mouth in the horizontal orientation. The device (width, 540 mm; depth, 65 mm; height, 35 mm; weight, 1.7 N) is made up of a flexible polyurethane with a natural frequency of 2-3Hz. Participants were asked to oscillate the device over a 15-s period in one of the following swings: (1) cervical flexion-extension and (2) knee flexion-extension. Both tasks were performed in a standing position. The order of the tasks performed by the participants was randomized. Data were collected twice for each task. The average EMG values were calculated during the tasks and then normalized relative to maximum voluntary contractions (%MVC). The paired t-test was used to examine the significance of differences between swings. P-values 0.05 were considered statistically significant.
Results: The activities (cervical flexion-extension and knee flexion-extension) of the sternocleidomastoid and cervical extensor muscles had 10.7 ± 6.5 and 5.7 ± 4.8 %MVC and 17.5 ± 10.3 and 12.2 ± 8.6 %MVC, respectively. Both muscles in knee flexion-extension present significantly low muscle activities than those in cervical flexion-extension.
Conclusion(s): The results of this study indicated that the task with knee flexion-extension had lower load for the cervical muscles than that with cervical flexion-extension.
Implications: The findings of this study should be considered when grading intensity of cervical coordination exercise.
Keywords: Electromyography, cervical muscles, oscillating blade
Funding acknowledgements: No external funding was received for this study.
Purpose: This study aimed to quantify the activities of the cervical muscles while using an oscillating blade held in the mouth with different swings.
Methods: Ten healthy male university students participated in this study (20.8 ± 0.9 years). The activities of the sternocleidomastoid and C4 cervical extensor muscles were measured using electromyography (EMG) for 5s while using an oscillating blade held in the mouth in the horizontal orientation. The device (width, 540 mm; depth, 65 mm; height, 35 mm; weight, 1.7 N) is made up of a flexible polyurethane with a natural frequency of 2-3Hz. Participants were asked to oscillate the device over a 15-s period in one of the following swings: (1) cervical flexion-extension and (2) knee flexion-extension. Both tasks were performed in a standing position. The order of the tasks performed by the participants was randomized. Data were collected twice for each task. The average EMG values were calculated during the tasks and then normalized relative to maximum voluntary contractions (%MVC). The paired t-test was used to examine the significance of differences between swings. P-values 0.05 were considered statistically significant.
Results: The activities (cervical flexion-extension and knee flexion-extension) of the sternocleidomastoid and cervical extensor muscles had 10.7 ± 6.5 and 5.7 ± 4.8 %MVC and 17.5 ± 10.3 and 12.2 ± 8.6 %MVC, respectively. Both muscles in knee flexion-extension present significantly low muscle activities than those in cervical flexion-extension.
Conclusion(s): The results of this study indicated that the task with knee flexion-extension had lower load for the cervical muscles than that with cervical flexion-extension.
Implications: The findings of this study should be considered when grading intensity of cervical coordination exercise.
Keywords: Electromyography, cervical muscles, oscillating blade
Funding acknowledgements: No external funding was received for this study.
Topic: Human movement analysis; Musculoskeletal; Musculoskeletal: spine
Ethics approval required: Yes
Institution: Kawasaki University of Medical Welfare
Ethics committee: Ethics Committee
Ethics number: 18-023
All authors, affiliations and abstracts have been published as submitted.
