Accession Number : ADA182148

Title :   Perceived Exertion under Conditions of Sustained Work and Sleep Loss.

Descriptive Note : Interim rept.,

Corporate Author : NAVAL HEALTH RESEARCH CENTER SAN DIEGO CA

Personal Author(s) : Ryman,David H ; Naitoh,P ; Englund,C E

PDF Url : ADA182148

Report Date : 25 Mar 1987

Pagination or Media Count : 22

Abstract : The relationships of perceived exertion (RPE) to workload, heart rate, and psychological measures during repeated treadmill walking while carrying 22kg have been analyzed in 2 studies. Exercising subjects alternated 30 min walks with 30 min of tasks for 16 one hr sessions on each of 2 consecutive days. Study 1 used an initial treadmill grade and speed producing 40% maximum oxygen consumption (VO2 max). This level was maintained until a subject could no longer complete a 30 min exercise session. Subsequently treadmill grade and then speed were reduced to a maintainable rate. Subjects got a 4 hr nap (Group 1) or rest (Group 2) between days. Study 2 used 30% VO2 max throughout and a 3 hr nap between days. One group started at midnight, the other at noon. Both studies showed a linear increase in RPE during each day (p .05) and a drop in RPE from the end of Day 1 to the start of Day 2 (p .001). Napping rather than just resting or starting at midnight rather than at noon did not change RPE. RPE was higher Day 2 than Day 1 in Study 2 (p .05). RPE increased through the stages of the maximal treadmill tests but did not vary among the 3 tests in Study 2. RPE was significantly correlated with heart rate, speed, and elevation gained (r and/or p) during most of Day 1 in Study 1 but not in Study 2. Psychological measures showed correlations with RPE only during the third 4 hr period of Day 1 in Study 1 for fatigue, vigor and sleepiness while these relationships persisted through most of Day 1 in Study 2.

Descriptors :   *SLEEP DEPRIVATION, *WORKLOAD, *STRESS(PHYSIOLOGY), *PSYCHOPHYSIOLOGY, ELEVATION, PSYCHOLOGY, TREADMILLS, WALKING, HEART RATE, STRESS TESTING, TREADMILLS

Subject Categories : Stress Physiology
      Personnel Management and Labor Relations

Distribution Statement : APPROVED FOR PUBLIC RELEASE