Chronic living at altitudes ~2500m causes consistent hematological acclimatization in most, but not all, groups of athletes; however, responses of erythropoietin (EPO) and red cell mass to a given altitude show substantial individual variability. We hypothesized that athletes living at higher altitudes would experience greater improvements in sea level performance, secondary to greater hematological acclimatization, compared to athletes living at lower altitudes. After 4 weeks of group sea level training and testing, 48 collegiate distance runners (32M, 16W) were randomly assigned to one of four living altitudes (1780m, 2085m, 2454m, or 2800m). All athletes trained together daily at a common altitude from 1250m - 3000m following a modified Live High - Train Low model. Subjects completed hematological, metabolic, and performance measures at sea level, before and after altitude training; EPO was assessed at various time points while at altitude. Upon return from altitude, 3000m time trial performance was significantly improved in groups living at the middle two altitudes (2085m and 2454m) but not in groups living at 1780m and 2800m. EPO was significantly higher in all groups at 24h and 48h, but returned to sea level baseline after 72h in the 1780m group. Erythrocyte volume was significantly higher within all groups after return from altitude, and was not different between groups. These data suggest that when completing a 4 week altitude camp following the Live High - Train Low model, there is a target altitude between 2000m and 2500m that produces an optimal acclimatization response for sea level performance.
- maximal oxygen uptake
- Copyright © 2013, Journal of Applied Physiology