Petrofsky J S, Lind A R
J Appl Physiol Respir Environ Exerc Physiol. 1978 Jul;45(1):64-8. doi: 10.1152/jappl.1978.45.1.64.
Three well-trained male subjects served as volunteers in these experiments to examine the physiological capacity for extended work during lifting tasks. The maximal oxygen uptake (VO2max) during lifting was always lower than work on the bicycle ergometer. However, the work load during lifting which could be maintained for 1--4 h was 50% of the VO2max for lifting each specific weight of box; the limit for lifting light boxes without fatigue was at an oxygen uptake of about 25% of the VO2max obtained from bicycle ergometry. Significant fatigue in the forearm muscles was found during prolonged lifting as assessed from the endurance of isometric contractions and from the surface electromyogram (EMG), and was more pronounced as the weight of the box increased.
在这些实验中，三名训练有素的男性受试者作为志愿者，以检验在搬运任务中进行长时间工作的生理能力。搬运过程中的最大摄氧量（VO2max）始终低于在自行车测力计上的工作。然而，在搬运过程中能够持续1至4小时的工作量是搬运每个特定重量箱子时VO2max的50%；搬运轻箱子且不疲劳的极限是摄氧量约为自行车测力计测得的VO2max的25%。从等长收缩耐力和表面肌电图（EMG）评估发现，长时间搬运过程中前臂肌肉出现明显疲劳，且随着箱子重量增加疲劳更明显。
