Aerobic Endurance Is More Highly Related To Load Carriage Performance Than Strength And Power

INTRODUCTION Police officers are required to carry external loads as part of their occupation. One means of preparing officers to carry loads is through physical conditioning. The aim of this study was to investigate whether strength, power or aerobic endurance had the greatest association with load carriage performance. METHODS Retrospective data from 42 male specialist tactical police officers (mean body weight = 88.8 ± 8.25 kg) informed this study. Baseline data were provided for strength (1 Repetition Maximum [RM] Bench Press, Deadlift, Squat and Pull up), lower body power (Vertical jump, 10 m sprint) and aerobic (‘beep’ test) performance. In addition, officers completed three 5 km load carriage trials (3 to 4 months apart) with 25 kg packs as fast as possible. Pearson’s correlations were used to investigate relationships between measures with an analysis of variance used to detect changes in load carriage performance. Alpha levels were set at 0.05 a priori. RESULTS All variables of strength and power were significantly correlated with performance except for 1 RM Deadlift and the 10 m sprint for the last two load carriage trials. Aerobic fitness was the most highly and significantly correlated variable with all three load carriage trials (r = -0.712, -0.709 and -0.711 for the three trials respectively) apart from the actual correlations amongst the load carriage trials themselves (Trial 2 r = 0.840, Trial 3 r = 0.815). Of the strength measures relative Pull ups were the most highly and significantly correlated variable (r = -0.607, -0.512, -0.541 for the three trials respectively). Time to complete the load carriage trials improved across the three trials (p < 0.001). CONCLUSIONS These findings support the approach that optimal load carriage performance may be achieved by performing load carriage tasks in conjunction with aerobic fitness and full body strength / lower limb power training.