This investigation evaluated the relationship between physical fitness and performance of fire suppression tasks. The following mean +/- SD values were associated with 91 fire fighters: age 31.69 +/- 7.39 years, height 177.29 +/- 6.38 cm, weight 83.97 +/- 10.86 kg, % fat 13.78 +/- 4.31, fat free weight (FFW) 71.52 +/- 7.66 kg, pull-ups 9.03 +/- 4.79, push-ups 41.02 +/- 14.08, 1.5 mile run 737.60 +/- 108.11 s, sit and reach 32.00 +/- 8.5 cm, sit-ups 39.88 +/- 7.75, and total grip strength 116.75 +/- 17.67 kg. The physical performance assessment (PPA) consisted of the following: stair climb, hoist, forcible entry, hose advance, and victim rescue. Significant correlations (p < 0.01) were found between the PPA and the following: total grip strength (r = -0.54), FFW (r = -0.47), height (r = -0.40), pull-ups (r = -0.38), push-ups (r = -0.38), 1.5 mile run (r = 0.38), sit-ups (r = -0.32), weight (r = -0.30) and % fat (r = 0.30). Multiple regression analysis indicated that the best multiple predictor of PPA was the 1.5 mile run, FFW, and pull-ups, r = 0.73, p < 0.001. This investigation shows the importance of physical fitness as related to performance of fire suppression job tasks.

Therefore, the HRV may not be related to the recovery of HR expressed as a slope (i.e., HRR) within 2 min following a maximal exercise test. This is possibly due to a significant inverse relationship between HRV and MHR, HR1 and HR2 post-maximal exercise.

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The purpose of this study was to determine if heart rate recovery (HRR) and heart rate variability (HRV) are related to maximal aerobic fitness and selected body composition measurements. Fifty men (age = 21.9 ± 3.0 years, height = 180.8 ± 7.2 cm, weight = 80.4 ± 9.1 kg, volunteered to participate in this study. For each subject, body mass index (BMI), waist circumference (WC), and the sum of skinfolds across the chest, abdomen, and thigh regions (SUMSF) were recorded. Heart rate variability (HRV) was assessed during a 5-minute period while the subjects rested in a supine position. The following frequency domain parameters of HRV were recorded: normalized high-frequency power (HFnu), and low-frequency to high-frequency power ratio (LF:HF). To determine maximal aerobic fitness (i.e., VO2max), each subject performed a maximal graded exercise test on a treadmill. Heart rate recovery was recorded 1 (HRR1) and 2 (HRR2) minutes during a cool-down period. Mean VO2max and BMI for all the subjects were 49.5 ± 7.5 ml·kg(-1)·min(-1) and 24.7 ± 2.2 kg·m(-2), respectively. Although VO2max, WC, and SUMSF was each significantly correlated to HRR and HRV, only SUMSF had a significant independent correlation to HRR1, HRR2, HFnu, LF:HF (p < 0.01). The results of the regression procedure showed that SUMSF accounted for the greatest variance in HRR1, HRR2, HFnu, and LF:HF (p < 0.01). The results of this study suggest that cardiovascular autonomic modulation is significantly related to maximal aerobic fitness and body composition. However, SUMSF appears to have the strongest independent relationship with HRR and HRV, compared to other body composition parameters and VO2max.

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