Developmental, genetic, and environmental components of aerobic capacity at high altitude

Abstract

The aerobic capacity of 268 subjects (158 males and 110 females) was evaluated in La Paz, Bolivia situated at 3,750 m. The sample included 1) 39 high altitude rural natives (all male); 2) 67 high altitude urban natives (32 male, 35 female); 3) 69 Bolivians of foreign ancestry acclimatized to high altitude since birth (37 male, 32 female); 4) 50 Bolivians of foreign ancestry acclimatized to high altitude during growth (25 male, 25 female); and 5) 42 non-Bolivians of either European or North American ancestry acclimatized to high altitude during adulthood (25 male, 18 female). Data analyses indicate that 1) high altitude urban natives, acclimatized to high altitude since birth or during growth, attained higher aerobic capacity than subjects acclimatized to high altitude during adulthood; 2) age at arrival to high altitude is inversely related to maximum oxygen consumption (VO2 max) expressed in terms L/min or ml/min/kg of lean body mass, but not in terms of ml/min/kg of body weight; 3) among subjects acclimatized to high altitude during growth, approximately 25% of the variability in aerobic capacity can be explained by developmental factors; 4) as inferred from evaluations of skin color reflectance and sibling similarities, approximately 20 to 25% of the variability in aerobic capacity at high altitude can be explained by genetic factors; 5) except among the non-Bolivians acclimatized to high altitude during adulthood, the aerobic capacity of individuals with high occupational activity level is equal to the aerobic capacity of high altitude rural natives; and 6) the relationship between occupational activity level and aerobic capacity is much greater among subjects acclimatized to high altitude before the age of 10 years than afterwards. Together these data suggest that the attainment of normal aerobic capacity at high altitude is related to both developmental acclimatization and genetic factors but its expression is highly mediated by environmental factors, such as occupational activity level and body composition.

Prevalence and Determinants of Hyperlipidemia in Moderate Altitude Areas of the Yunnan-Kweichow Plateau in Southwestern China

“…The mean BMI measurement in our present study (23.1 -3.2) is comparable with that reported previously for Chinese adults in rural plain area of Tianjin (23.7 -3.8) (Huiguang Tian et al, 2009) and for rural Bolivians (22.7 -0.4) (Frisancho et al, 1995), although the value is lower than that described for high-altitude Quechua populations from the Peruvian Central Andes (24.2 -2.1) (Toselli, 2001) and the SPC district of Peru (25.4 -3.7) (Mohanna et al, 2006). The WHRs measured in our current study were 0.85 -0.08 for the total group, 0.89 -0.08 in men and 0.82 -0.06 in women, which are different from those of other reports: 0.90 -0.09 in men and 0.91 -0.10 in women in a population-based sample of 12,514 (Das et al, 2010).…”

Human high-altitude adaptation: forward genetics meets the HIF pathway

“…When measured at high altitude, individuals of low-altitude ancestry who are born and raised at high altitude do not exhibit differences in their SaO 2 levels compared with individuals of low-altitude ancestry who are born and raised at low altitude (Dempsey et al 1971;Frisancho et al 1995). For example, European sojourners to high altitude exhibit similar SaO 2 values compared with Europeans born and raised at high altitude (Brutsaert et al 2000), thus suggesting that there are no developmental effects of chronic hypoxia exposure on SaO 2 .…”

Developmental adaptation: Where we go from here

“…Since the residual volume plays a major role in the oxygen uptake the fact that is attained before adulthood illustrates that the adult lung volumes are determined by the developmental factors. The enlarged residual lung volume or large alveolar area because its role on the supply of oxygen and the excretion of carbon dioxide contributes to the normal aerobic capacity that characterize high-altitude natives (Brutsaert et al, 2004;Frisancho et al, 1995;Hurtado, 1964).…”