{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,15]],"date-time":"2026-07-15T05:49:14Z","timestamp":1784094554549,"version":"3.55.0"},"reference-count":58,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2026,1,1]],"date-time":"2026-01-01T00:00:00Z","timestamp":1767225600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Federal Ministry of Research, Technology and Space of Germany","award":["16DHBKI011"],"award-info":[{"award-number":["16DHBKI011"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Altitude training camps are a popular measure to enhance endurance performance at sea level. This study elucidates the effects of acute altitude-induced hypoxia, running speed and surface on cadence, peak tibial acceleration (PTA), gait asymmetry and residual shock in distance running. Ten healthy, trained native lowlanders (6 males, 4 females; 28.2 \u00b1 9.2 years; mean V\u02d9O2,peak of 54.9 \u00b1 5.9 mL min\u22121 kg\u22121) participated in this study. They ran 1500 m bouts of at 50, 1000 and 2300 m above mean sea level on paved roads and natural trails at three different speeds. Those speeds were chosen to represent the most common training zones and were defined as v1=90%\u22c5vVT1, v2=12vVT1+vVT2 and v3=100%\u22c5vVT2, with vVT1 and vVT2 denoting the speeds at the ventilatory thresholds 1 and 2. Based on the experimental results, cadence increased by +2.2 spm per +1 km h\u22121 (p &lt; 0.001) and fell by \u22121.1. spm per +1000 m of elevation (p &lt; 0.001), whereas surface did not show any significant effect. Likewise, PTA was not affected by surface, but grew by 0.9 g per +1 km h\u22121 (p &lt; 0.001), and decreased by \u22120.6 g per +1000 m in elevation, with significant effects particularly at speeds beyond vVT1 (p &lt; 0.049). Absolute lateral asymmetry was not altered by elevation, surface or running speed. Mean shock attenuation increased with running speed by +2.5 percentage points per +1 km h\u22121 (p &lt; 0.001) but was independent of elevation and surface. In essence, running speed seems to be the predominant factor defining biomechanical loading, even under acute hypoxia and for varying surface conditions.<\/jats:p>","DOI":"10.3390\/s26010276","type":"journal-article","created":{"date-parts":[[2026,1,2]],"date-time":"2026-01-02T09:56:23Z","timestamp":1767347783000},"page":"276","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Effects of Acute Altitude, Speed and Surface on Biomechanical Loading in Distance Running"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6822-5201","authenticated-orcid":false,"given":"Olaf","family":"Uebersch\u00e4r","sequence":"first","affiliation":[{"name":"Department of Engineering and Industrial Design, Magdeburg-Stendal University of Applied Sciences, 39114 Magdeburg, Germany"},{"name":"Institute for Applied Training Science, 04109 Leipzig, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-2322-9097","authenticated-orcid":false,"given":"Marlene","family":"Riedl","sequence":"additional","affiliation":[{"name":"Department of Engineering and Industrial Design, Magdeburg-Stendal University of Applied Sciences, 39114 Magdeburg, Germany"},{"name":"Department of Orthopaedic and Trauma Surgery, Martin Luther University Halle-Wittenberg, 06120 Halle, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniel","family":"Fleckenstein","sequence":"additional","affiliation":[{"name":"Institute for Applied Training Science, 04109 Leipzig, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9956-7538","authenticated-orcid":false,"given":"Roberto","family":"Falz","sequence":"additional","affiliation":[{"name":"Department of Engineering and Industrial Design, Magdeburg-Stendal University of Applied Sciences, 39114 Magdeburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"249","DOI":"10.2165\/00007256-200131040-00002","article-title":"Current Trends in Altitude Training","volume":"31","author":"Wilber","year":"2001","journal-title":"Sports Med."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1651","DOI":"10.1007\/s40279-019-01165-y","article-title":"Contemporary Periodization of Altitude Training for Elite Endurance Athletes: A Narrative Review","volume":"49","author":"Mujika","year":"2019","journal-title":"Sports Med."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"107","DOI":"10.2165\/00007256-200939020-00002","article-title":"Sea-level exercise performance following adaptation to hypoxia: A meta-analysis","volume":"39","author":"Bonetti","year":"2009","journal-title":"Sports Med."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"837","DOI":"10.1152\/japplphysiol.00663.2013","article-title":"Timing of return from altitude training for optimal sea level performance","volume":"116","author":"Chapman","year":"2014","journal-title":"J. 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