Effects of Heavy Personal Protection Equipment on Muscle Activation and Motor Behavior During Explosive Ordnance Disposal Operations

Abstract

Objective

To investigate muscle activation and movement behavior in the lower back and legs during selected explosive ordnance disposal (EOD) operational tasks to evaluate the impact of EOD personal protective equipment (PPE) on performance and the body.

Background

EOD PPE is designed to shield technicians from blast-related threats. However, the protective features make the PPE heavy, and restrictive to movement. It remains unclear how wearers adapt their movement under these constraints.

Method

Sixteen participants performed six EOD operational tasks ranked the most challenging and frequently encountered. Electromyography (EMG), force plates, and motion capture system were used to measure the movement while the tasks were performed with and without wearing EOD PPE.

Results

EMG results show task-dependent, asymmetrical muscle activation, with greater demands during physically intensive tasks such as bending, lifting, and stair climbing. A trend of decreased ankle muscle activation was observed when carrying a heavy load. Reduced center of pressure displacement was noted during tasks such as bending and rising from kneeling.

Conclusion

Wearing EOD PPE amplifies muscle demands, particularly in the thigh muscles during movements requiring postural adjustment and lifting and may increase stiffness or restrict movement. Elevated thigh muscle activity across tasks, together with restricted mobility, increases the hip’s vulnerability to overuse and musculoskeletal injury.

Application

Altered motor behavior from wearing EOD PPE has implications for other PPE uses. Understanding human motor adaptation during operations supports prevention strategies such as exoskeletons, ergonomic designs, and targeted training, to reduce musculoskeletal strain, sustain performance, and protect long-term health.