Research Center in Back, Neck, Other Joint Pain and Human Performance, Khon Kaen University, Khon Kaen, Thailand; School of Physical Therapy, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, Thailand.
Research Center in Back, Neck, Other Joint Pain and Human Performance, Khon Kaen University, Khon Kaen, Thailand; School of Physical Therapy, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, Thailand.
Appl Ergon. 2021 Sep;95:103458. doi: 10.1016/j.apergo.2021.103458. Epub 2021 May 12.
Smartphone use is a risk factor for both neck and shoulder musculoskeletal disorders. The objective of this study was to evaluate an ergonomic arm support prototype device, which may help improve posture while using a smartphone, by determining its effect on muscle activity, muscle fatigue, and neck and shoulder discomfort. Twenty-four healthy young adult smartphone users performed 20 min of smartphone game playing under two different conditions, smartphone use with support prototype device (i.e. intervention condition) and without (i.e. control condition), while neck and shoulder posture were controlled at 0° neck flexion and 30° shoulder flexion. Activity and fatigue of four muscles were measured using surface electromyography (sEMG), these were: anterior deltoid (AD), cervical erector spinae (CES), upper trapezius (UT) and lower trapezius (LT). The intervention condition showed significantly decreased activity of all muscles. Fatigue of all muscles, except LT, significantly increased over time compared to the start point in the control condition. There was no significant difference in muscle fatigue between each time point in the intervention condition. In conclusion, the ergonomic arm support prototype device can be used as ergonomic intervention to reduce neck and shoulder muscle loading and fatigue.
智能手机的使用是导致颈部和肩部肌肉骨骼疾病的一个风险因素。本研究旨在评估一种符合人体工程学的手臂支撑原型设备，该设备可通过改善使用智能手机时的姿势，从而帮助缓解颈部和肩部的不适，同时减少肌肉疲劳和肌肉活动。24 名健康的年轻智能手机用户在两种不同条件下（使用原型设备和不使用原型设备）各进行 20 分钟的智能手机游戏，在此过程中，颈部和肩部姿势保持在 0°颈椎前屈和 30°肩部前屈。通过表面肌电图（sEMG）测量了四块肌肉（三角肌前束、颈伸肌、上斜方肌和下斜方肌）的活动和疲劳情况。结果显示，与对照组相比，在干预组中，所有肌肉的活动都显著减少。与对照组相比，除了下斜方肌之外，所有肌肉的疲劳在试验过程中都随着时间的推移而显著增加。在干预组中，不同时间点之间的肌肉疲劳没有显著差异。综上所述，该符合人体工程学的手臂支撑原型设备可作为一种干预措施，以减少颈部和肩部肌肉的负荷和疲劳。
