Abstract Background Home, public transport, work, the number of environmental positions constraining the use of smartphones is significant. Research question How can the presence of an upper limb support influence the sitting posture of smartphone users under fixed illumination and brightness? Methods Twelve subjects (21,6 ± 5,5 years old) performed web browsing under two environmental positions (POSITION): sitting with and without support (table). The users' postures were evaluated through relative kinematics joint angles analysis. A repeated measure analysis of variance and Tukey post-hoc tests were performed to test the effect of POSITION on posture. Results In sitting position in front of a table, neck is less stressed (flexion Relevance to industry To prevent injury or pain, the use of an upper limb support (to lean on) should be considered for people/workers who use the smartphone frequently.

中文翻译：

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当智能手机用户在环境光线条件下处于坐姿时，上肢支撑的存在与否对姿势的影响

摘要背景家庭、公共交通、工作、环境职位的数量限制了智能手机的使用。研究问题 在固定照度和亮度下，上肢支撑的存在如何影响智能手机用户的坐姿？方法 12 名受试者（21.6 ± 5.5 岁）在两种环境姿势（POSITION）下进行网页浏览：坐着和没有支撑（桌子）。通过相对运动学关节角度分析来评估用户的姿势。进行了方差的重复测量分析和 Tukey 事后检验，以测试 POSITION 对姿势的影响。结果 坐在桌子前，颈部压力较小（屈曲与行业相关为了防止受伤或疼痛，