caa a22 4500 467941017 CHVBK 20180406153012.0 cr unu---uuuuu 170328e20060301xx s 000 0 eng 10.1007/s00421-005-0081-9 doi (NATIONALLICENCE)springer-10.1007/s00421-005-0081-9 Linear decrease in $$\dot V\hbox{O}_{2\max}$$ and performance with increasing altitude in endurance athletes [Elektronische Daten] [Jon Wehrlin, Jostein Hallén] It has been hypothesized that one reason for decreased $$\dot V\hbox{O}_{2\max}$$ in hypoxia could be the lower maximal exercise intensity achieved in incremental, time or distance trial tests. We hypothesized that (1) $$\dot V\hbox{O}_{2\max}$$ would be decreased at altitude even when exercising at the same absolute maximal exercise intensity as at sea level and; (2) the decline in $$\dot V\hbox{O}_{2\max}$$ in endurance-trained athletes (ETA) would be linear across the range from sea level through moderate altitudes. Eight ETA performed combined $$\dot V\hbox{O}_{2\max}$$ and performance tests running to exhaustion at the same speed in a randomized double blind fashion at simulated altitudes of 300, 800, 1,300, 1,800, 2,300 and 2,800m above sea level using a hypobaric chamber. Douglas bag system was used for respiratory measurements and pulse oximetry was used to estimate arterial O2 saturation. $$\dot V\hbox{O}_{2\max}$$ declined linearly from 66±1.6mlkg−1min−1 at 300m to 55±1.6ml kg−1min−1 at 2,800m corresponding to a 6.3% decrease per 1,000m increasing altitude (range 4.6-7.5%). Time to exhaustion (performance) at a constant velocity associated with 107% of sea level $$\dot V\hbox{O}_{2\max}$$ decreased with 14.5% (P<0.001) per 1,000m altitude between 300 and 2,800m. Both $$\dot V\hbox{O}_{2\max}$$ and performance decreased from 300 to 800m (P<0.01; P<0.05). Arterial haemoglobin oxygen saturation at test cessation (SpO2min) declined from 89.0±2.9% at 300m to 76.5±4.0% at 2,800m (P=0.001). This study report that in ETA during acute exposure to altitude both performance and $$\dot V\hbox{O}_{2\max}$$ decline from 300 to 800m above sea level and continued to decrease linearly to 2,800m. Springer-Verlag, 2005 Hypoxia nationallicence Time to exhaustion nationallicence Oxygen uptake nationallicence Arterial oxygen saturation nationallicence Exercise nationallicence Wehrlin Jon Norwegian School of Sport Sciences, Ullevål Stadion, PO box 4014, 0806, Oslo, Norway aut Hallén Jostein Norwegian School of Sport Sciences, Ullevål Stadion, PO box 4014, 0806, Oslo, Norway aut European Journal of Applied Physiology Springer-Verlag 96/4(2006-03-01), 404-412 1439-6319 96:4<404 2006 96 421 https://doi.org/10.1007/s00421-005-0081-9 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00421-005-0081-9 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Wehrlin Jon Norwegian School of Sport Sciences, Ullevål Stadion, PO box 4014, 0806, Oslo, Norway aut NATIONALLICENCE 700 1- Hallén Jostein Norwegian School of Sport Sciences, Ullevål Stadion, PO box 4014, 0806, Oslo, Norway aut NATIONALLICENCE 773 0- European Journal of Applied Physiology Springer-Verlag 96/4(2006-03-01), 404-412 1439-6319 96:4<404 2006 96 421 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer