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Improving Body Composition May Reduce the Immune and Inflammatory Responses of Firefighters Working in the Heat
Anthony Walker1, Heather E Wright Beatty, Sara Zanetti
1University of Canberra Research Institute for Sport and Exercise (Drs Walker, Rattray); Australian Capital Territory Fire & Rescue (Dr Walker); Flight Research Laboratory, Aerospace, National Research Council Canada, Ottawa, Canada (Dr Beatty); and Discipline of Sport and Exercise Science, Faculty of Health (Ms Zanetti, Dr Rattray), University of Canberra, Canberra, Australia.
Objective:
We hypothesized that different body composition and fitness of firefighters would affect immune and inflammatory activity after working in the heat.
Methods:
Forty-two firefighters worked in the heat (100 ± 5 °C). Changes in leukocytes, platelets, tumor necrosis factor (TNF-α), and C-reactive protein (CRP) were analyzed based on body composition (DXA) and aerobic fitness (VO2max).
Results:
Higher baseline leukocytes were observed for high body fat (P = 0.002) and low lean mass (P = 0.023) resulting in the highest peak values. Additionally, significantly lower values for TNF-α were observed with high lean mass at all time points. Platelets were unaffected by fitness or body composition. Furthermore, body mass index (BMI) and VO2max played no role.
Conclusions:
Minimizing body fat and increasing lean mass may reduce immune and inflammatory activity of firefighters in the heat.
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