{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,1]],"date-time":"2026-06-01T16:09:47Z","timestamp":1780330187807,"version":"3.54.1"},"reference-count":45,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2020,8,25]],"date-time":"2020-08-25T00:00:00Z","timestamp":1598313600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JFMK"],"abstract":"<jats:p>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 (LTP1) 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 (LTP1; LTP2) and ventilatory thresholds (VT1; VT2). Heart rate (HR) recordings were obtained during one eight-hour shift (HR8h) 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 (Pmax), maximal oxygen consumption (VO2 max) and power output at LTP1 and LTP2 were significantly different between male and female workers. HR8h was not significantly different between male and female workers. A significant relationship was found between Pmax and power output at LTP1. HR8h as a percentage of maximum HR significantly declined with increasing performance (Pmax:r = \u22120.56; p &lt; 0.01; PLTP1:r = \u22120.49; p &lt; 0.01). Despite different cardio-respiratory fitness-levels; 95.4% of all workers performed their usual work below LTP1. It is therefore suggested that LTP1 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.<\/jats:p>","DOI":"10.3390\/jfmk5030066","type":"journal-article","created":{"date-parts":[[2020,8,25]],"date-time":"2020-08-25T09:30:07Z","timestamp":1598347807000},"page":"66","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["The First Lactate Threshold Is a Limit for Heavy Occupational Work"],"prefix":"10.3390","volume":"5","author":[{"given":"Patrick","family":"Fasching","sequence":"first","affiliation":[{"name":"Private Clinic Maria Hilf, Radetzkystra\u00dfe 35, 9020 Klagenfurt, Austria"},{"name":"Center for Occupational Medicine AMEZ, Hergottwiesgasse 149, 8055 Graz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stefan","family":"Rinnerhofer","sequence":"additional","affiliation":[{"name":"Center for Occupational Medicine AMEZ, Hergottwiesgasse 149, 8055 Graz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Georg","family":"Wultsch","sequence":"additional","affiliation":[{"name":"Center for Occupational Medicine AMEZ, Hergottwiesgasse 149, 8055 Graz, Austria"},{"name":"Medical University of Graz, Auenbruggerplatz 2, 8036 Graz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Philipp","family":"Birnbaumer","sequence":"additional","affiliation":[{"name":"Institute of Human Movement Science, Sport and Health, University of Graz, Max-Mell-Allee 11, 8010 Graz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4836-1238","authenticated-orcid":false,"given":"Peter","family":"Hofmann","sequence":"additional","affiliation":[{"name":"Institute of Human Movement Science, Sport and Health, University of Graz, Max-Mell-Allee 11, 8010 Graz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,8,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"233","DOI":"10.5271\/sjweh.3354","article-title":"The Contribution of Overweight, Obesity, and Lack of Physical Activity to Exit from Paid Employment: A Meta-Analysis","volume":"39","author":"Robroek","year":"2013","journal-title":"Scand. 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