Assessment of Physical Activity Intensity by Heart Rate during Sleep Limited Military Operations

摘要

This study estimated the intensity of physical activity of infantrymen by means of continuous heart rate (HR) recordings during a combat-simulated 5-day field operation. Subjects rotated daily through 4 different combat-simulated field maneuver areas and repeated the first day's schedule on the fifth day. Soldiers slept approximately 5 hours per night and physical activity was monitored by taping HR with Oxford-Medilog cassette recorders. Daily HR (excluding sleep and resupply time) decreased to a mean of 101 beats per min (bpm) on day one to a mean of 89 bpm on day five. A 10 km road march proved to be the single most demanding event resulting of this study suggest (1) continuous cassette HR recording is a suitable method of monitoring the intensity of physical activity during strenuous field conditions (2) sustained high physical intensity is minimal in infantrymen during extended field operations, (3) this intensity of activity is adequately supported by an aerobic capacity of 50 ml o2/kg.min, (4) the highest sustained HR is produced by marches or movements to contact, and (5) the physical fatigue and diminished sleep of combat operations may force infantrymen to perform at a slower rate regardless of operational demands as the exercise progresses.