Physical activity and aerobic fitness level in children living at high altitude in Tibet

Aim. The present study aimed to determine objectively measured physical activity levels and aerobic fitness using direct measurements of peak oxygen uptake (aerobic fitness) in a sample of children living at high altitude, in Lhasa, Tibet Autonomous Region, China. Methods. Twenty-five Tibetan and 15 Han Chinese school children (9-10 yrs old) living in Lhasa, 3658 metre above sea level, performed maximal cycling on a cycle ergometer with oxygen uptake measurements. Peak oxygen uptake was defined as aerobic fitness. The participants also wore an activity monitor, SenseWear™ Pro ₂ Armband (BodyMedia, Inc., Pittsburgh, PA, USA) for six consecutive days. Results. All children fulfilled the physical activity recommendations, which recommend children to be daily physically active for at least 60 minutes. Moderate-vigorous physical activity (MVPA) was significantly higher (P=0.04) in boys (Median and 95% Confidence Intervals; 5.0 (2.6, 7.3) hours per day) vs. girls (3.1 (2.6, 4.5) hours per day), respectively. Tibetan boys had higher MVPA compared to Han Chinese boys although not significant. Boys had significantly higher (P<0.001) aerobic fitness compared to girls (47.3 (43.4, 52.1) vs. 40.4 (37.2, 42.9) ml·kg ^-1·min ^-1, respectively. There were no significant differences in aerobic fitness between Tibetan and Han Chinese children. Conclusion: The children living at high altitude included in the present study were fit and physically active.