Text

Introduction: Firefighting is a physically demanding profession that exposes workers to high risks of work-related musculoskeletal disorders (WMSDs) due to repetitive heavy lifting, awkward postures, and sustained physical exertion. Traditional physical assessments are performed annually but fail to capture real-time fluctuations in physical capacity, potentially increasing the risk of injuries. Velocity-based strength monitoring offer a promising approach to continuously assessing fatigue and performance, enabling timely intervention to prevent WMSDs. This study evaluates the validity and reliability of RepOne, a digital velocity-tracking tool, for real-time monitoring of firefighters’ physical performance and fatigue.

Methods: A total of 20 firefighters will perform three occupationally relevant strength exercises (deadlift, pull-up, and high row) while velocity metrics are recorded using RepOne. Construct validity will be assessed by comparing RepOne’s measurements with performance outcomes from the Danish standardized annual firefighter fitness certification, and fatigue detection will be assessed by measuring velocity loss and perceived exertion during repetitions to voluntary exhaustion. To establish criterion validity, 20 strength-trained university students and 20 firefighters will perform the same exercises under Vicon 3D motion capture, the gold standard in motion analysis. Test-retest reliability will be evaluated to determine measurement consistency.

Results: Data collection will take place between April and June 2025. Preliminary results regarding the validity, reliability, and appropriateness of RepOne for fatigue and performance monitoring will be presented at the conference.

Discussion: If valid, RepOne could serve as an accessible and time-efficient tool for monitoring physical performance and early signs of fatigue in firefighters. By providing continuous data-driven insights, this technology may help prevent WMSDs and enhance long-term occupational health and safety in a physically demanding profession.

Conclusion: Real-time monitoring of physical performance using RepOne may offer a novel approach for preventing WMSDs in firefighters by enabling early detection of fatigue. Future research should explore broader applications of velocity-based monitoring in first responder occupations.