Body Composition Is Related to Maximal Effort Treadmill Test Time in Firefighters.

Firefighting tasks may require near maximal levels of cardiorespiratory fitness. Previous research has indicated that body fat percentage (BF%) and aerobic capacity (VO) are related to the performance of firefighting tasks. Since a standard submaximal treadmill test for firefighters is terminated at 85% of maximal heart rate (MHR), key performance information relating to maximal cardiorespiratory effort may not be measured in a submaximal test. The purpose of this study was to examine the relationships between body composition and time spent running at intensities greater that 85% MHR. Height, weight, body mass index (BMI; kg/m), BF%, MHR (bpm), VO (mL/kg/min), predicted VO (P-VO; mL/kg/min), submaximal treadmill test time (WFI Test Time; min), and maximal treadmill test time (WFI Test Time; min) were collected in fifteen active-duty firefighters. The results indicated that significant relationships ( < 0.05) existed between BF% and VO, BF% and WFI Test Time, BF% and T, and VO and WFI Test Time. P-VO was not significantly different than VO, and the WFI Test Time was significantly longer than the WFI Test Time. These results indicate that a submaximal treadmill test may reasonably predict VO, but key information about physiological work at intensities greater than 85% MHR may be missed when using submaximal effort tests.