Prediction of military relevant occupational tasks in women from physical performance components

摘要

This study sought to determine through multiple regression analysis which measures were most predictive for a repetitive box lifting task (RBLT) and for a load bearing task (LBT) (i.e. 2 mile, 34.1 kg military rucksack carry) in 113 women (23+-4 yrs, 165+-7 cm, 64+-10 kg). The RBLT consisted of the maximum number of boxes (20.45 kg) that could be lifted from the floor to a height of 1.32 m within a 10 min period (subjects were required to move between two boxes 2.4 m apart between lifts). The LBT consisted of the minimum time to traverse 2 miles while carrying a 34.1 kg military style rucksack. Independent variables (IVs) included body mass, height, magnetic resonance imaging assessed leg cross-sectional area, muscular strength 1 RMs (squat, bench press, high pull, boxlift), lower body explosive power (mechanical power assessed via jump squats), muscular endurance ( of push ups in 2 min and of squat repetitions at a controlled rate with a 45 kg load [squat endurance test]) and aerobic capacity assessed from a 2 mile run (2MR in secs). The mean+-SD (range) for the RBLT ( of repetitions) was: 86+-23 (20-159) and for the LBT (in seconds) was: 2054+-340 (1307-3447). The following equations were generated (p<=0.05): RBLT ( of repetitions)=57.4+0.2 (peak jump power) + 0.4( of push-ups in 2 min) + 0.15( of repetitions during the squat endurance test) +1.39 (IRM boxlift in kg) - 0.04 (2 MR in secs) [R=0.81; SEE=14]; LBT (in seconds)=1831-4.28 ( of repetitions during the squat endurance test) + 0.95 (2MR in seconds) - 13.4 (body mass) [R=0.73; SEE=232]. The fact that the 2MR and squat endurance test entered into both equations illustrates their utility as potential predictors for successful military occupational performance. These data also suggest that women can augment their performance in physically demanding occupations by participating in conditioning programs targeting both muscular strength and endurance.