Metabolic accommodation of young children to treadmill walking

Few data exist concerning the reproducibility of stable oxygen uptake (VO2) values during level treadmill walking in, young able-bodied children. To a ddress this issue, 41 able-bodied 6-year-olds (19 boys, 22 girls, X height = 117.2 +/- 4.7 cm, X body mass = 21.8 +/- 2.5 kg) were tested on two occas ions. In session 1, subjects were familiarized with the laboratory environm ent and performed 5 min of level treadmill walking at 1.34 m s(-1). During session 2, each child completed 30 min (three 10-min trials) of level tread mill walking at 1.34 m s(-1). For each 10-min trial, mean VO2 was determine d by averaging VO2 values obtained from analysis of two 2-min expired gas s amples. While the mean VO2 for trial 1 was higher than values recorded for trials 2 and 3, effect sizes corresponding to these differences were low ( less than or equal to 0.16). Average within subject coefficient of variatio n and intraclass reliability coefficient values for VO2 across the three wa lking trials were 2.0 +/- 1.5% and 0.96, respectively. Viewed collectively, these results suggests that among young able-bodied children, acceptably a nd reproducible stable VO2 values during level treadmill walking can be obt ained within 10 min if data collection is preceded by exposure to testing p rocedures and a brief period of treadmill walking practice. (C) 2000 Elsevi er Science B.V. All rights reserved.