핸드폰 사용이 목과 어깨 근육의 근육활성도와 피로도에 미치는 영향 = The Effect of Using Smart-Phones on Neck and Shoulder Muscle Activities and Fatigue

국문 초록 (Abstract)

본 연구는 성인 남자 17명을 대상으로 스마트폰을 장기간 사용하였을 때 목과 어깨 근육의 피로도 정도를 알아보았다. 20분 이상 핸드폰을 사용할 경우 양쪽 위등세모근과 목세움근의 중앙주파수가 유의하게 감소하였으며 양쪽 목세움근과 오른쪽 위등세모근의 근활성도(50th%APDF)가 유의하게 증가하였다. APDF범위는 양쪽 목세움근과 위등세모근 모두 유의하게 증가하였다. 이는 스마트폰을 20분 이상 사용하게 되면 피로도가 증가한다는 것을 나타낸다. 따라서 스마트폰 사용자는 스마트폰 사용 시 올바른 자세를 취하고, 중간에 휴식과 스트레칭 등의 예방적 행동을 취하기를 권고한다.

다국어 초록 (Multilingual Abstract)

The smart-phone has become a necessity for most people. In this study, we determined that using a smart-phone for 20 minutes can cause increased neck and shoulder muscle activities and fatigue. Seventeen healthy male smart-phone users who attended Yonsei University played a smart-phone game for 20 minutes and changes in their bilateral cervical erector spinae and upper trapezius muscle activities and fatigue were measured. To assess muscle activities and fatigue, we used the following variables: the median frequency, the 50th percentile Amplitude probability distribution function (APDF) value (median load), and the discrepancy in the 90th percentile APDF value and the 10th percentile APDF value (APDF range). A paired t-test was used to compare pre-smart-phone-use status with post-smart-phone-usestatus. The median frequency of the bilateral cervical erector spinae and the upper trapezius decreased significantly after 20 minutes of smart-phone use (p<.05). In addition, the 50th percentile APDF value of the bilateral cervical erector spinae and the right upper trapezius increased significantly (p<.05). The APDF range of the bilateral cervical erector spinae and the upper trapezius also increased significantly (p<.05). However, the 50th percentile APDF range of the left upper trapezius was not significantly different (p>.05). These findings suggest that using smart-phones for 20 minutes can induce muscle fatigue and increased neck and shoulder muscle activities.

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