Live high-train low altitude training: responders and non-responders

Objective: Investigate differences between athletes that responded (improved performance) compared to those that did not, after a 20-day “live high-train low” (LHTL) altitude training camp. Methods: Ten elite triathletes completed 20 days of live high (1545-1650 m), train low (300 m) training. The athletes underwent (i), two 800-m swimming time trials at sea-level (1 week prior to and 1 week after the altitude camp) and (ii) two 10-min standardised submaximal cycling tests at altitude on day 1 and day 20 of the altitude camp. Acute mountain sickness (AMS) was also measured during the camp. Based on their 800-m swimming time trial performances, athletes were divided into responders (improved by 3.2 ± 2.2%, mean ± SD, n=6) and non-responders (decreased by 1.8 ± 1.2%, n=4). Results: Compared to non-responders, the responders had lower exercise heart rates (-6.3 ± 7.8%, mean ± 90% CL, and higher oxygen saturations (1.2 ± 1.3%) at the end of the 10-min submaximal test after the camp. Compared to the responders, the non-responders had substantially higher VE and VE/VO₂ during the submaximal test on day 1 of the altitude training camp, and a substantially higher RER during the submaximal test on day 20 of the camp. As a result of the altitude training, exercise economy of the non-responders compared to the responders deteriorated (i.e., non-responders required more oxygen per watt). Non-responders were 3.0 times (90% CL=0.5-16.6) more likely to suffer symptoms of acute mountain sickness during first 5 days of altitude compared to responders. Conclusion: Changes in SpO₂, heart rate and some respiratory variables during exercise and resting AMS scores may help determine athletes that respond to LHTL altitude training camps from athletes that fail to respond to such training