Most firefighters wear heavily insulated rubber boots or lighter leather boots. A five to 12% increase in oxygen consumption per kg of weight added to the foot has been observed; however, the increase may depend on gender, boot material, and whether or not subjects are wearing additional protective clothing or equipment.
PURPOSE: To determine the effects of two leather (L1, L2) and two rubber (R1, R2) boots on firefighters' metabolic and respiratory variables during simulated firefighting tasks.
METHODS: Eighteen women and 21 men, while wearing full turnout gear and one of four randomly assigned pairs of firefighter boots, walked for six minutes at three mph on a treadmill while carrying a 9.5-kg hose and then climbed a stair ergometer for six minutes at 45 steps/min. Minute ventilation (VE), oxygen consumption (VO2 and VO2kg), CO2 production (VCO2), and heart rate (HR) were measured, and an average of breath-by-breath data from minute six was used for analysis of covariance with repeated measures.
RESULTS: During treadmill exercise, boot weight had a significant effect (p ≤ < 0.05) on VO2 and VO2kg for men only (*), whereas boot weight had a significant effect (p ≤ 0.05) on VE and VCO2 for both men and women (**). There were no significant effects of boot weight during stair climbing. There were no significant effects of boot material on any variables during either mode of exercise.
CONCLUSION: During treadmill exercise, each additional kg of boot weight was associated with a significant 6.5% increase in VE for both men and women and with a significant 8% increase in VO2 and VO2kg for men only.
Disclaimer: “The findings and conclusions in this abstract have not been formally disseminated by NIOSH and should not be construed to represent any agency policy.
