Psychophysical frequency and sustained exertion at varying wrist postures for a drilling task.

摘要: Abstract Two laboratory experiments were conducted; first, to utilize the psychophysical approach (method of adjustment) establish maximum acceptable frequency (MAF) for a sheet metal drilling task and, second, examine effect sustained, static exertion upon objective and subjective measures under similar conditions. In both experiments, wrist posture (flexation, ulnar deviation) required by was varied. Twelve healthy females served as subjects. Results show that adjusted significantly lower when deviation required, particularly flexion. MAF one-third (25°) two-thirds (50°) flexion 88% 73%, respectively, those selected in neutral posture. Furthermore, these results supported trends grip strength, heart rate, blood pressure, EMG perceived exertion. from sustained trials revealed significant increases physiological parameters occurred during 3-minute sessions ...