Fasching Patrick, Rinnerhofer Stefan, Wultsch Georg, Birnbaumer Philipp, Hofmann Peter
Private Clinic Maria Hilf, Radetzkystraße 35, 9020 Klagenfurt, Austria.
Center for Occupational Medicine AMEZ, Hergottwiesgasse 149, 8055 Graz, Austria.
J Funct Morphol Kinesiol. 2020 Aug 25;5(3):66. doi: 10.3390/jfmk5030066.
Long-term heavy physical work often leads to early retirement and disability pension due to chronic overload, with a need to define upper limits. The aim of this study was to evaluate the value of the first lactate threshold (LTP) as a physiological marker for heavy occupational work. A total of 188 male and 52 female workers performed an incremental cycle ergometer test to determine maximal exercise performance and the first and second lactate (LTP; LTP) and ventilatory thresholds (VT; VT). Heart rate (HR) recordings were obtained during one eight-hour shift (HR) and oxygen uptake was measured during 20 minutes of a representative work phase. Energy expenditure (EE) was calculated from gas-exchange measures. Maximal power output (P), maximal oxygen consumption (VO) and power output at LTP and LTP were significantly different between male and female workers. HR was not significantly different between male and female workers. A significant relationship was found between P and power output at LTP. HR as a percentage of maximum HR significantly declined with increasing performance (P:r = -0.56; < 0.01; P:r = -0.49; < 0.01). Despite different cardio-respiratory fitness-levels; 95.4% of all workers performed their usual work below LTP. It is therefore suggested that LTP represents the upper limit for sustained heavy occupational work; which supports its use to determine work capability and assessing the limits of heavy occupational work.
长期繁重的体力劳动常常因慢性负荷过重导致提前退休和领取残疾抚恤金，因此需要确定上限。本研究的目的是评估第一乳酸阈值（LTP）作为繁重职业工作生理标志物的价值。共有188名男性和52名女性工人进行了递增式自行车测力计测试，以确定最大运动能力以及第一和第二乳酸（LTP；LTP）和通气阈值（VT；VT）。在一个八小时轮班期间记录心率（HR），并在一个代表性工作阶段的20分钟内测量摄氧量。根据气体交换测量结果计算能量消耗（EE）。男性和女性工人之间的最大功率输出（P）、最大耗氧量（VO）以及LTP和LTP时的功率输出存在显著差异。男性和女性工人之间的心率没有显著差异。发现P与LTP时的功率输出之间存在显著关系。随着运动能力的提高，心率占最大心率的百分比显著下降（P：r = -0.56；<0.01；P：r = -0.49；<0.01）。尽管心肺适能水平不同，但所有工人中有95.4%在LTP以下进行日常工作。因此，建议LTP代表持续繁重职业工作的上限，这支持将其用于确定工作能力和评估繁重职业工作的限度。
