Exercise Physiology Lab, Kinesiology Department, California State University Monterey Bay, Seaside, California, USA.
J Strength Cond Res. 2010 Feb;24(2):307-12. doi: 10.1519/JSC.0b013e3181c8c84e.
The objective of the revised NIOSH (National Institute for Occupational Safety and Health) lifting equation is to prevent or reduce lifting-related injuries. The coupling component of the equation relates to quality of the grip (i.e., hand-to-object interface) and can be rated good, fair, or poor. Good coupling is theorized to reduce lifting stress, whereas poor coupling is theorized to increase lifting stress. This study compared the physiological and psychophysical stress between a lifting task with identical weight but different coupling factors. Subjects (n = 21; 26 +/- 6 years; 177.8 +/- 7.8 cm; 73.9 +/- 10.7 kg) transferred a milk crate or bag of dog food each weighing 12.5 kg back and forth from the floor to a table for 2, paced, 5-minute work bouts. Steady-state metabolic data were used to compare the lifting tasks. Results showed significantly higher oxygen consumption, caloric cost, heart rate, and rating of perceived exertion during the lifting task using the milk crate vs. the bag of dog food (p < 0.05). No difference in respiratory exchange ratio was observed (p > 0.05). In conclusion, a significantly higher metabolic cost and perceived exertion was observed when subjects performed a paced two-handed lifting task with good coupling factors than when using an object with poor coupling factors. When lifting stress is measured by metabolic cost and perceived exertion, these results are in contrast to expectations that a poor quality grip (i.e., poor coupling) would increase stress of a lifting task. Results of this study may help the work-place practitioner make decisions related to the use of the revised NIOSH lifting equation in the design and pacing of lifting-related tasks. Improved decision making may benefit productivity and enhance injury prevention in the workplace.
修订后的 NIOSH（美国国家职业安全与健康研究所）举重方程的目的是预防或减少与举重相关的伤害。该方程的耦合组件与握持质量（即手与物体的界面）有关，可评为良好、中等或差。良好的耦合被认为可以降低举重的压力，而较差的耦合则被认为会增加举重的压力。本研究比较了具有相同重量但不同耦合因素的举重任务的生理和心理压力。研究对象（n = 21；26 +/- 6 岁；177.8 +/- 7.8 厘米；73.9 +/- 10.7 公斤）将一个牛奶箱或一袋重 12.5 公斤的狗粮来回从地板上搬到一张桌子上，每个工作回合持续 2 分钟，速度固定。使用稳态代谢数据比较举重任务。结果表明，使用牛奶箱进行举重任务时，耗氧量、热量消耗、心率和感知用力程度明显高于使用狗粮袋（p < 0.05）。呼吸交换比无差异（p > 0.05）。总之，当研究对象进行具有良好耦合因素的 paced 双手举重任务时，观察到代谢成本和感知用力明显高于使用具有较差耦合因素的物体时。当通过代谢成本和感知用力来衡量举重压力时，这些结果与预期的较差握持质量（即较差的耦合）会增加举重任务压力的期望相反。本研究的结果可能有助于工作场所的从业者在设计和安排与举重相关的任务时，根据修订后的 NIOSH 举重方程做出决策。改进的决策可能有利于提高工作效率并在工作场所预防伤害。
