Effect of acute altitude exposure on ventilatory thresholds in recreational athletes

• Published in: Respiratory physiology & neurobiology 2021-11, Vol.293, p.103723-103723, Article 103723
• Main Authors: Schüttler, Dominik, Weckbach, Ludwig T., Hamm, Wolfgang, Maier, Florian, Kassem, Sari, Schier, Johannes, Lackermair, Korbinian, Brunner, Stefan
• Format: Article
• Language: English
• Subjects: Adult; Altitude; Anaerobic Threshold - physiology; Athletes; Cross-Sectional Studies; Exercise; Exercise - physiology; Exercise Test; Female; High altitude; Humans; Hypobaric hypoxic condition; Hypoxia - physiopathology; Male; Recreation; Recreational athletes; Respiration; Training zone; Ventilatory thresholds
• ISSN: 1569-9048; 1878-1519
• DOI: 10.1016/j.resp.2021.103723

•The effect of hypobaric hypoxic exposure on ventilatory thresholds is insufficiently explored so far in recreational athletes.•Anaerobic threshold and ventilatory compensation point show a clear left shift during hypobaric hypoxic exercise.•VT-guided training has thus to be adapted when training an altitude. High altitude (HA) training is frequently used in endurance sports and recreational athletes increasingly participate in cross mountain competitions. At high altitude aerobic physiology changes profoundly. Ventilatory thresholds (VTs) are measures for endurance performance but the impact of exposure to acute altitude (AA) on VTs in recreational athletes has been insufficiently explored to date and most studies investigated effects under normobaric hypoxia. In this cross-sectional study we investigated the effects of AA exposure at 2650 m/715 mbar on anerobic threshold (VT1) and respiratory compensation point (VT2) in a graded cycling test in 14 recreational athletes (4 female, 10 male) compared to baseline levels (521 m, 949 mbar). At VT1, a decline in power output (PO) from median 115.5 W to 105.0 W (median -12.3 %, p = 0.032; Wilcoxon test) during exposure to HA was observed. VO2/body weight and VO2/heart rate decreased markedly (- 9.5 %, p = 0.016; -10.5 %, p = 0.012). At VT2 we found a significant decline of PO from 184.5–170.5 W (-13.1 %, p = 0.0014), of VO2/body weight and of VO2/heart rate (-10.1 %, p = 0.0015; -8.7 %, p = 0.002) compared to baseline values. Absolute VO2 decreased (-9.5 %, p = 0.0014 and -10.1 %, p = 0.0002) while minute ventilation and heart rates remained unchanged at both thresholds. Our data allows a quantification of performance loss at HA in recreational athletes and demonstrates that VT-guided training intensities and workloads need to be adapted for training at HA.