Spine loading during laboratory-simulated fireground operations - inter-individual variation and method of load...

Area of Science:

• Occupational Health
• Biomechanics
• Ergonomics

Background:

• Firefighters face high physical demands, necessitating research into spine loading during operations.
• Understanding spine load variations is critical for developing effective, low-back health-preserving interventions.

Purpose of the Study:

• To quantify spine loads during simulated fireground operations.
• To compare spine load variations between 20 individual firefighters performing the same tasks.
• To evaluate both simple and advanced methods for spine load quantification.

Main Methods:

• Utilized simple (polynomial) and advanced (EMG-assisted musculoskeletal model) methods to measure spine loads.
• Quantified compression and shear forces (anteroposterior and mediolateral) during simulated tasks.
• Analyzed the variability of spine loads across 20 participants.

Main Results:

• Spine compression forces varied up to 5.5 times bodyweight between individuals.
• Shear forces showed significant variation, up to 3.2 times bodyweight (anteroposterior) and 2.1 times bodyweight (mediolateral).
• High variability in spine loads was observed irrespective of the quantification method used.

Conclusions:

• Individual firefighters experience widely varying low-back loading demands due to physical characteristics and movement strategies.
• Personalized ergonomic interventions, including exercise and movement retraining, are recommended.
• Addressing individual differences is key to regulating spine loading and enhancing load tolerance.