Exploring the Interaction Between Head-Supported Mass, Posture, and Visual Stress on Neck Muscle Activation

Abstract

Objective Assess neck muscle activity for varying interactions between helmet, posture, and visual stress in a simulated “helo-hunch” posture. Background Military aviators frequently report neck pain (NP). Risk factors for NP include head-supported mass, awkward postures, and mental workload. Interactions between these factors could induce constant low-level muscle activation during helicopter flight and better explain instances of NP. Method Interactions between physical loading (helmet doffed/donned), posture (symmetric/asymmetric), and visual stress (low/high contrast) were studied through neck muscle electromyography (EMG), head kinematics, subjective discomfort, perceived workload, and task performance. Subjects ( n = 16) performed eight 30-min test conditions (varied physical loading, posture, and visual stress) while performing a simple task in a simulated “helo-hunch” seating environment. Results Conditions with a helmet donned had fewer EMG median frequency cycles (which infer motor unit rotation for rest/recovery, where more cycles are better) in the left cervical extensor and left sternocleidomastoid. Asymmetric posture (to the right) resulted in higher normalized EMG activity in the right cervical extensor and left sternocleidomastoid and resulted in less lateral bending compared with neutral across all conditions. Conditions with high visual stress also resulted in fewer EMG cycles in the right cervical extensor. Conclusion A complex interaction exists between the physical load of the helmet, postural stress from awkward postures, and visual stress within a simulated “helo-hunch” seating environment. Application These results provide insight into how visual factors influence biomechanical loading. Such insights may assist future studies in designing short-term administrative controls and long-term engineering controls.

Design guidelines for limiting and eliminating virtual reality-induced symptoms and effects at work: a comprehensive, factor-oriented review

“…According to this factor, adapting interactions for less tiring gestures could help prevent fatigue (Li G. et al, 2020) MF_3 IV HMD weight HMD weight seems to add physical stress on the cheekbone and back of the head (Kim and Shin, 2018;Yan et al, 2019). Wearing a helmet during screen use induces neck pain (Le et al, 2021) Chose the lighter HMD, or try to alleviate weight (Kim and Shin, 2018;Yan et al, 2019) MF_4 VI…”

Toward Optimized VR/AR Ergonomics: Modeling and Predicting User Neck Muscle Contraction

“…Consequently, muscular discomfort [Chihara and Seo 2018;Forde et al 2011;Penumudi et al 2020;Souchet et al 2022], especially in the neck and shoulders [Kim and Shin 2018;Marklin Jr et al 2022], may be induced. Prior research has studied the impacts of headsupported mass on neck muscle activities under various application scenarios to better design dedicated hardware devices [Le et al 2021;Rubine-Gatina et al 2022;Thuresson et al 2005Thuresson et al , 2003, such as military helmets. Complementing advances in hardware designs, we focus on modeling and predicting muscle activities under the VR/AR settings, where visual stimuli are controllable and optimizable, to guide the design of virtual content for better ergonomic comfort.…”

Neck Muscle Coactivation Response to Varied Levels of Mental Workload During Simulated Flight Tasks

“…With respect to aviation, visual displays within the cockpit and helmet-mounted systems are common to enhance human–machine teaming and augment workloads (Bayer et al, 2009). However, depending on the information flow and visual stress induced, these systems can potentially increase mental workload, which have been associated with increased neck muscle tension (Hoyle et al, 2011; Le et al, 2021; Treaster et al, 2006). The concern is primarily due to prolonged muscle tension response which can accelerate fatigue, stimulate nociceptors, and potentially lead to injury due to feedback control errors to external perturbations (Kim et al, 2018; Le et al, 2021; Le & Weisenbach, 2022; Visser & van Dieën, 2006).…”

“…However, depending on the information flow and visual stress induced, these systems can potentially increase mental workload, which have been associated with increased neck muscle tension (Hoyle et al, 2011; Le et al, 2021; Treaster et al, 2006). The concern is primarily due to prolonged muscle tension response which can accelerate fatigue, stimulate nociceptors, and potentially lead to injury due to feedback control errors to external perturbations (Kim et al, 2018; Le et al, 2021; Le & Weisenbach, 2022; Visser & van Dieën, 2006). In addition to visual stimuli, multiple demands from resource management, communications, vigilance, and aircraft control can magnify the mental workload (Wickens, 1991) and thereby the subsequent muscle response depending on the mission set.…”