F. Yang, Air Force Health Care Center for Special Services, Hangzhou, China.
W. Tan, Y. Tian, Q. Wu, X. Feng, G. Hu, et al
Physiol Rep 2026 Vol. 14 Issue 8 Pages e70864
To evaluate altitude-stratified differences in static lung function, aerobic capacity, and exercise physiology under standardized normoxic conditions, and identify multiple predictors of peak oxygen uptake (VO2) reduction among asymptomatic men after prolonged residence at varying altitudes. We conducted a cross-sectional study of 103 asymptomatic men stratified by residential altitude: low (<2500 m; n = 35), high (2500-3500 m; n = 32), and very high (>3500 m; n = 36). All underwent spirometry, fasting blood tests, and symptom-limited cardiopulmonary exercise testing (CPET) in normoxia. Multiple linear regression identified independent predictors of peak VO2/kg. Very high-altitude residents had significantly lower peak VO2/kg (-13.4 mL·min-1·kg-1 vs. low altitude, p < 0.001), reduced oxygen pulse, and impaired small-airway function (MMEF, FEF75; p < 0.05), despite preserved ventilatory efficiency (VE/VCO2 slope, p = 0.782). Hemoglobin was elevated at higher altitudes; triglycerides were higher only above 3500 m. Age (β = -0.285), regular exercise (≥3 sessions/week; β = +3.648), and very high-altitude residence (β = -13.370) independently predicted peak VO2/kg (all p < 0.001; R2 = 0.739). Residence above 3500 m causes persistent cardiopulmonary impairment driven by circulatory limitations and smoking, despite preserved ventilatory efficiency. Normoxic assessment identifies regular exercise (≥3 sessions/week) as a key countermeasure against altitude-induced deconditioning. Prioritizing smoking cessation and mandatory exercise programs is therefore recommended for long-term health in high-altitude personnel.