The pulmonary oxygen uptake response is deleteriously influenced by obesity in prepubertal children, as evidenced by a slower phase II response. To date, no studies have investigated the ability of an exercise intervention to ameliorate this. The objective of the study was to investigate the influence of a 6-week, high-intensity, games-orientated intervention on the oxygen uptake kinetic response of prepubertal obese and normal-weight children during heavy-intensity exercise. Thirteen normal-weight and 15 obese children participated in a twice-weekly exercise intervention involving repeated bouts of 6-min high-intensity, games-orientated exercises followed by 2 min of recovery. Sixteen normal-weight and 11 obese children served as a control group. At baseline and post-intervention, each participant completed a graded-exercise test to volitional exhaustion and constant work-rate, heavy-intensity exercise. Post-intervention, obese children demonstrated a reduced phase II τ (pre-intervention: 30 ± 8 cf. post-intervention: 24 ± 7 s), mean response time (pre-intervention: 50 ± 10 cf. post-intervention: 38 ± 9 s) and phase II amplitude (pre-intervention: 1.51 ± 0.30 cf. post-intervention: 1.34 ± 0.27 L·min(-1)). No changes were evident in the normal-weight children. In conclusion, the present findings demonstrate that a 6-week, high-intensity intervention can have a significant positive impact on the dynamic oxygen uptake response of obese prepubertal children.
Keywords: BMI; IMC; V̇O2 kinetics; cinétique du O2; entraînement; exercise intensity; games; high intensity; intensité de l’exercice; intensité élevée; jeux; training.