RESEARCH ARTICLE Comparison of ‘‘Live High-Train Low’ ’ in

We investigated the changes in both performance and selected physiological parameters following a Live High-Train Low (LHTL) altitude camp in either normobaric hypoxia (NH) or hypobaric hypoxia (HH) replicating current ‘‘real’’ practices of endurance athletes. Well-trained triathletes were split into two groups (NH, n514 and HH, n513) and completed an 18-d LHTL camp during which they trained at 1100–1200 m and resided at an altitude of 2250 m (PiO25121.7¡1.2 vs. 121.4¡0.9 mmHg) under either NH (hypoxic chamber; FiO2 15.8¡0.8%) or HH (real altitude; barometric pressure 580¡23 mmHg) conditions. Oxygen saturations (SpO2) were recorded continuously daily overnight. PiO2 and training loads were matched daily. Before (Pre-) and 1 day after (Post-) LHTL, blood samples, VO2max, and total haemoglobin mass (Hbmass) were measured. A 3-km running test was performed near sea level twice before, and 1, 7, and 21 days following LHTL. During LHTL, hypoxic exposure was lower for the NH group than for the HH group (220 vs. 300 h; P,0.001). Night SpO2 was higher (92.1¡0.3 vs. 90.9¡0.3%