Objective

To investigate the effect of one’s sex and pedaling intensity on upper body muscle activation patterns during typing while cycling.

Background

Females are at a higher risk for computer work-related musculoskeletal disorders, and mobile workstations have been suggested to induce healthier muscular patterns compared with sitting. However, the neuromuscular characteristics of performing computer work in a cycling workstation have not been investigated.

Method

Twenty-two participants (10 females) completed a 60-min computer typing task while pedaling on a cycle ergometer at two different intensities (25%, 4% heart rate reserve). Surface electromyography (EMG) was recorded from seven muscles of the upper body. Effects of time, sex, and intensity were assessed for muscle activation (RMS), activation variability (CV), and normalized mutual information (NMI) via generalized estimating equations.

Results

With time, neck/shoulder CV increased in males during higher pedaling intensity, whereas in females it decreased during lower intensity. In females, RMS of neck/shoulder and NMI of neck/shoulder muscle pairs were lower, whereas forearm RMS was 34.2% higher with higher intensity cycling compared with lower intensity. Lower back RMS decreased 28.3% in the initial half of the task in females, but in males it increased 14.4% in the later half.

Conclusion and application

Cycling workstation showed a sex- and intensity-specific EMG response. These differing responses should be considered when implementing the use of cycling workstation and may be important for preventing/managing sex-specific muscle fatigue and musculoskeletal disorders.

中文翻译：

---

打字时骑自行车对上半身肌肉激活模式的影响

客观的

调查一个人的性别和踩踏强度对骑车打字时上半身肌肉激活模式的影响。

背景

女性患计算机工作相关肌肉骨骼疾病的风险更高，与坐着相比，移动工作站被认为可以诱导更健康的肌肉模式。然而，尚未研究在自行车工作站中执行计算机工作的神经肌肉特征。

方法

22 名参与者（10 名女性）完成了 60 分钟的电脑打字任务，同时以两种不同的强度（25%、4% 心率储备）踩踏自行车测力计。从上半身的七块肌肉记录表面肌电图 (EMG)。通过广义估计方程评估时间、性别和强度对肌肉激活 (RMS)、激活变异性 (CV) 和归一化互信息 (NMI) 的影响。

结果

随着时间的推移，男性的颈部/肩部 CV 在较高踩踏强度时增加，而女性在较低强度时降低。在女性中，颈部/肩部的 RMS 和颈部/肩部肌肉对的 NMI 较低，而与较低强度相比，高强度骑行的前臂 RMS 高 34.2%。在女性任务的前半部分，腰部 RMS 下降了 28.3%，但在男性任务的后半部分，它增加了 14.4%。

结论与应用

自行车工作站显示出性别和强度特定的 EMG 反应。在实施自行车工作站的使用时应考虑这些不同的反应，并且可能对预防/管理性别特异性肌肉疲劳和肌肉骨骼疾病很重要。