Cardiorespiratory Fitness of Firefighters: Initial Results of a Multi-Phased Study.

OBJECTIVE: To address which body composition (BC) measures best correlate with cardiorespiratory fitness (CRF) in firefighters and develop a model for accurate CRF estimation compared with traditional methods. METHODS: Career firefighters had body mass index (BMI) and waist circumference (WC) measured in addition to body fat percentage (FM%) by dual-energy x-ray absorptiometry (DXA). CRF as maximum oxygen uptake (VO2max) was estimated by rowing machine and measured by indirect calorimetry in a treadmill exercise test. RESULTS: Fifty two firefighters participated (92.3% men). Univariate correlations with BMI were best with WC. Univariate correlations with VO2max were best with FM%. Obesity classifications by BC measures agreed weakly at best. Multivariate analysis of several variables yielded an improved VO2max estimate (R2 = 0.70). CONCLUSIONS: Fire departments may benefit from more sophisticated measures of BC and CRF to evaluate firefighter fitness.

Temporal artery temperature measurements do not detect hyperthermic marathon runners.

INTRODUCTION: Exertional heat stroke is a cause of collapse in marathon runners. Rectal temperature (T(rectal)) measurement is the usual method of estimating core temperature in collapsed runners, and temporal artery thermometer (TAT) measurement is untested for field use in marathon runners and other athletes. The objective of this study is to compare TAT measurement with T(rectal) measurement in collapsed marathon runners. METHODS: TAT-500i (Exergen Corp, Wellesley, MA) temperature measurements were obtained using the manufacturer's instruction manual on 60 collapsed marathon runners who had T(rectal) measurements in the finish area medical tent during two consecutive annual races. RESULTS: The TAT temperatures identified only 2 of 17 hyperthermic runners (T(rectal) > 39.4 degrees C (103 degrees F)), a sensitivity of only 0.12, and a Pearson' correlation coefficient of 0.374 (r = 0.14). Among the 17 hyperthermic runners, the correlation of T(rectal) to TAT temperatures was 0.526 (r = 0.28) with a mean +/- SD T(rectal) of 40.7 +/- 0.94 degrees C (105.1 +/- 1.7 degrees F) and a mean +/- SD TAT temperature of 37.4+/- 1.3 degrees C (99.4 +/- 2.4 degrees F). Among the 43 collapsed normothermic runners, there was no correlation between the rectal and the TAT measurements (r = -0.142, P = 0.37). CONCLUSIONS: These findings indicate that there is little association between the temperatures obtained by temporal artery measurement and T(rectal) measurement in collapsed marathon runners and that TAT temperature is unable to identify hyperthermic runners. Based on these findings, TAT measurement should not be used to assess core body temperature or make treatment decisions for marathon runners with potential exertional heat stroke.