title: Defining the "dose" of altitude training: how high to live for optimal sea level performance enhancement.
abstract: Chronic living at altitudes of ∼2,500 m 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 with athletes living at lower altitudes. After 4 wk of group sea level training and testing, 48 collegiate distance runners (32 men, 16 women) were randomly assigned to one of four living altitudes (1,780, 2,085, 2,454, or 2,800 m). All athletes trained together daily at a common altitude from 1,250-3,000 m 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. On return from altitude, 3,000-m time trial performance was significantly improved in groups living at the middle two altitudes (2,085 and 2,454 m), but not in groups living at 1,780 and 2,800 m. EPO was significantly higher in all groups at 24 and 48 h, but returned to sea level baseline after 72 h in the 1,780-m 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-wk altitude camp following the live high-train low model, there is a target altitude between 2,000 and 2,500 m that produces an optimal acclimatization response for sea level performance.
authors.affiliation: Department of Kinesiology, Indiana University, Bloomington, Indiana;
authors.forename: Robert F
authors.initials: RF
authors.lastname: Chapman
authors.forename: Trine
authors.initials: T
authors.lastname: Karlsen
authors.forename: Geir K
authors.initials: GK
authors.lastname: Resaland
authors.forename: R-L
authors.initials: RL
authors.lastname: Ge
authors.forename: Matthew P
authors.initials: MP
authors.lastname: Harber
authors.forename: Sarah
authors.initials: S
authors.lastname: Witkowski
authors.forename: James
authors.initials: J
authors.lastname: Stray-Gundersen
authors.forename: Benjamin D
authors.initials: BD
authors.lastname: Levine
mesh_terms: D000064:Acclimatization; D000531:Altitude; D054874:Athletic Performance; D015415:Biomarkers / Q000097:blood; D004912:Erythrocytes / Q000378:metabolism; D004921:Erythropoietin / Q000097:blood*; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D010101:Oxygen Consumption; D064797:Physical Conditioning, Human / Q000379:methods*; D012123:Pulmonary Ventilation; D012420:Running; D013997:Time Factors; D055815:Young Adult
chemical_list: D015415:Biomarkers; C554270:EPO protein, human; D004921:Erythropoietin
keywords: athletes; erythropoietin; maximal oxygen uptake