Description:
The Australian Defence Force (ADF) has resolved to establish a series of physical employment standards for Infantry soldiers and Airfield Defence Guards. A key stage in establishing these standards is to analyse the physical requirements of the two jobs. The purpose of this study was to analyse the physical requirements of the key physical tasks required within the two jobs. The jobs were divided into over 100 component tasks. Some tasks were common to the two jobs while others were specific to the respective jobs. ADF subject matter experts identified 36 tasks that were considered to be the most physically demanding. These tasks were observed to determine the movement patterns (actions) and muscle groups involved, the duration, velocity and estimated of exercise intensity. An estimate was also made of the involvement of each of seven activity types (endurance, strength-endurance etc) in each task and the exercise volume contained within each task. The tasks were ranked based upon the volume of work involved within each classification of activity type and movement action. Based upon these analyses, a series of tasks were chosen as those which best reflected the range of physical requirements of an Infantry soldier and an Airfield Defence Guard. These tasks were: marching while carrying support weapons, carrying ammunition boxes, assaulting, wall climbing, sandbagging, jumping from a height, pursuiting, rope climbing, patrolling in an urban environment, population protection, patrolling in marching order, building forced entry and stair climbing, casualty evacuation, loading stores and digging.
Description:
Aim. The aim of the study was to determine the effects of volume and intensity of static stretching in a warm-up on explosive force production and range of motion (ROM) of the plantar flexors. Methods. Twenty subjects performed 5 warm-ups on different days. The warm-ups contained a 5 min treadmill run and various protocols of 30 s static stretches (SS) of the plantar flexors. Stretching involved dorsi flexion just before the pain threshold, which was considered 100% intensity. The treatments that immediately followed the run were: (i) no other treatment (control); (ii) 1 min SS; (iii) 2 min SS; (iv) 4 min SS; (v) 2 min SS at 90% intensity. Ankle ROM was assessed before and after each warm-up and a concentric calf raise and drop jump (DJ) test was conducted after each warm-up. Results. There were no significant differences (P>0.05) in peak force or rate of force production in the explosive calf raise between any of the warm-ups. However the run plus 2 min stretch and the run plus 4 min stretch protocols produced significantly lower (P<0.05) DJ performance (jump height/ground contact time) than the run. The run plus 4 min stretch warm-up also produced a significantly lower DJ score than the run plus 1 min stretch warm-up. There were no significant differences between any of the warm-ups in ankle ROM. Conclusions. The addition of 2-4 min of SS at 100% intensity to a run caused an impairment to fast stretch shortening cycle muscle performance. The greater impairment from the 4 min stretching condition supported a volume-effect. Two minutes of stretching at 90% intensity had no significant influence on muscle function. The addition of up to 4 min of SS to a run had no appreciable effect on ankle ROM, possibly because of the prior influence of the run.