The influence of a six-week, high-intensity games intervention on the pulmonary oxygen uptake kinetics in prepubertal obese and normal-weight children

Abstract

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.

Ergogenic effects of beetroot juice supplementation during severe-intensity exercise in obese adolescents

“…Other factors contributing to the impaired exercise tolerance in obesity include a higher O 2 cost for submaximal exercise (30,33,37), which is at least in part attributable to an increased O 2 cost of breathing (31,32), a lower GET, slower adjustment of the fundamental component of V O 2 kinetics (30), and a more pronounced amplitude of the slow component of V O 2 kinetics during heavy-intensity exercise (30). At least in part, these impairments can be overcome by exercise training (24), including training specifically directed toward respiratory muscles (31).…”

Análisis del componente rápido de la cinética de recuperación del consumo de oxígeno tras un programa HIIT de 10 días en un grupo de obesos

“…Con respecto a ésto, McNarry, et al 48 investigaron la influencia de un HIIT sobre la cinética del VO 2 en obesos adolescentes, y los resultados indicaron diferencias significativas en el tau de la cinética on luego del periodo de intervención, lo cual sustenta la evidencia hallada, considerando que los mecanismos responsables del aumento de la cinética rápida son similares en ambas fases on-off. Además, al comparar la relación entre el VO 2 pico y el tau on, considerados ambos como marcadores de fitness aeróbico, no se encontraron mejoras significativas en el VO 2 pico, sugiriendo que aquello se podría deber a los factores predominantes para cada variable; factores intrínsecos musculares (relacionados a la cinética) y factores cardiovasculares centrales (relacionados al VO 2 pico).…”

“…Con respecto a los factores musculoesqueléticos, Salvadego, et al 34 , mencionan un aumento en la proporción de fibras musculares rápidas, las que son menos resistentes a la fatiga, comparadas a las fibras tipo I. Además, poseen un menor contenido y capacidad mitocondrial, lo que tiene directa relación con la pobre tolerancia al ejercicio en los sujetos obesos. Esto último, se manifiesta en la respuesta dinámica pulmonar del VO 2 , en donde se reconoce una cinética menor comparado con sujetos sanos o sujetos entrenados 43,48 . La cinética del VO 2 refleja la tasa de cambio que se experimenta al variar la demanda y requerimientos metabólicos, de acuerdo a la actividad física realizada, lo que para los sujetos obesos ocurre frecuentemente en actividades de la vida diaria.…”

Muscle Oxygenation During Exercise in Physically Active and Overweight 6–19-Year-Old Children

“…13-17-year-old boys demonstrate significant changes in absolute hemoglobin concentrations and oxygenation in the exercising muscle during incremental cycling and post-exercise recovery (Ganesan et al, 2016). 9-year-old girls demonstrate an earlier change in [HHb] compared with same age boys during ramp incremental exercise (McNarry et al, 2015). Also, prepubertal, pubertal, postpubertal trained girls demonstrate a significant rightward shift in the sigmoidal response of [HHb] compared with untrained girls (McNarry et al, 2010).…”

“…Ventilatory anaerobic threshold and maximal oxygen uptake related to body weight are lower in the obese than in normal weight 9-14-year-old children (Zanconato et al, 1989). The pulmonary oxygen uptake response is deleteriously influenced by obesity in prepubertal children (McNArry, Lambrick, Westrupp, & Faulkner, 2015). Obese children demonstrate significantly slower VO 2 kinetics compared to normal weight children during moderate-and heavy intensity exercise (Lambrick, Faulkner, Westrupp, & McNarry 2013).…”