INFLUENCE OF AMBIENT TEMPERATURE ON THE CONTROL OF BODY POSTURE STABILITY IN PROFESSIONAL FIREFIGHTERS
Authors: Dolibog Patrycja , Dolibog Paweł , Biel Tomasz , Pietrzyk Barbara 
Published: December 2024

Introduction. Stability of body posture is essential for ensuring safety and achieving highphysical performance. Firefighting, as a high-risk occupation, exposes professionals to factorsthat destabilize balance and posture, increasing the risk of falls and injuries. Extreme thermalenvironments are known to affect postural stability, which relies on dynamic neuromuscularcontrol influenced by vision, body temperature, and psychophysiological state.Objective. This study aims to assess the influence of ambient temperature on the control of bodyposture stability among professional firefighters. Specifically, it examines the role of visual controlin balance maintenance and explores coordination between the nervous and musculoskeletalsystems using posturographic measurements from a force plate (AccuGait). Additionally, thestudy investigates the relationships between posturographic parameters, heart rate (HR), heartrate variability (HRV) and body temperature. The impact of extreme thermal conditions –temperatures exceeding 35C and falling below 0C – on balance maintenance, dizziness, andbalance disorders is also analysed.Material and Methods. Seventeen healthy male volunteers (mean age 35.9 6.1 years, mean workexperience 10.7 5.5 years) were involved in the study. In the first phase, participants completeda survey containing general and detailed questions. They responded with “YES” or “NO” regardingtheir exposure to high temperatures (above 35C) and low temperatures (below 0C). In the secondphase, measurements were taken using the AccuGait force plate (AMTI, USA). Each participantperformed two 30-second trials. The first trial involved standing still on the force plate with openeyes (OE) and closed eyes (CE). Heart rate (HR) and heart rate variability (HRV) were monitoredusing a Polar H7 heart rate monitor and the EliteHRV application. Additionally, infrared photos ofall participants were taken using a FLIR C3X Compact thermal camera.Results. The study revealed that 89.7% of respondents reported experiencing dizziness duringexposure to high temperatures. Force plate testing confirmed excellent postural stability amongfirefighters in both open-eye (OE) and closed-eye (CE) trials. In the CE trial, an 18.9% increase in the average COP velocity (Avg Velocity) and a 19.3% increase in COP path length (Length)were observed. The average heart rate (HR) for the 17 participants was 79.9 15 beats per minute.A correlation was identified between HR and the average COP velocity, COP path length, andthe minimal COP deviation along the Y-axis (AP). The average heart rate variability (HRV) was56.4 8.8 ms, and HRV correlated with the maximum COP value on the Y-axis (AP) during theCE trial. The average corneal temperature was 34.4 1.5C. Statistical analysis was conductedusing Spearman’s rank correlation and the Wilcoxon signed-rank test.Conclusions. The risk of balance disturbances is higher when firefighters operate in hightemperatureenvironments (above 35C) as compared to low temperatures (below 0C). Theabsence of visual control does not compromise the stability of firefighters’ posture, reflecting theirexceptional neuromuscular coordination. The dynamics of muscle force activation in maintainingbody balance are influenced by visual control status and heart rate.