Individual variation in response to altitude training

TLDR

Although the mean improvement with the high‑low training model is clear, individual responses vary widely. The study aimed to identify factors underlying this variability by retrospectively classifying 39 collegiate runners as responders or nonresponders based on changes in sea‑level 5,000‑m run time after 28 days of moderate‑altitude living and training. Participants were divided into responder and nonresponder groups, and a separate prospective cohort of 22 elite runners was examined to validate the identified factors. Responders showed a markedly larger acute erythropoietin surge after 30 h at altitude, leading to increased red cell volume and V˙o₂max, while nonresponders had no such changes and experienced reduced interval‑training velocity and oxygen consumption; a prospective cohort confirmed these differences, indicating that altitude training benefits depend on achieving a substantial Epo rise and maintaining low‑altitude training intensity.

Abstract

Moderate-altitude living (2,500 m), combined with low-altitude training (1,250 m) (i.e., live high-train low), results in a significantly greater improvement in maximal O 2 uptake (V˙o 2 max ) and performance over equivalent sea-level training. Although the mean improvement in group response with this “high-low” training model is clear, the individual response displays a wide variability. To determine the factors that contribute to this variability, 39 collegiate runners (27 men, 12 women) were retrospectively divided into responders ( n = 17) and nonresponders ( n = 15) to altitude training on the basis of the change in sea-level 5,000-m run time determined before and after 28 days of living at moderate altitude and training at either low or moderate altitude. In addition, 22 elite runners were examined prospectively to confirm the significance of these factors in a separate population. In the retrospective analysis, responders displayed a significantly larger increase in erythropoietin (Epo) concentration after 30 h at altitude compared with nonresponders. After 14 days at altitude, Epo was still elevated in responders but was not significantly different from sea-level values in nonresponders. The Epo response led to a significant increase in total red cell volume andV˙o 2 max in responders; in contrast, nonresponders did not show a difference in total red cell volume or V˙o 2 max after altitude training. Nonresponders demonstrated a significant slowing of interval-training velocity at altitude and thus achieved a smaller O 2 consumption during those intervals, compared with responders. The acute increases in Epo and V˙o 2 max were significantly higher in the prospective cohort of responders, compared with nonresponders, to altitude training. In conclusion, after a 28-day altitude training camp, a significant improvement in 5,000-m run performance is, in part, dependent on 1) living at a high enough altitude to achieve a large acute increase in Epo, sufficient to increase the total red cell volume andV˙o 2 max , and 2) training at a low enough altitude to maintain interval training velocity and O 2 flux near sea-level values.