Acute Effect of Fatmax Exercise on the Metabolism in Overweight and Nonoverweight Girls

Abstract

A bout of Fatmax exercise performed ~16 h before high-glycemic-index breakfast consumption reduced fasting and postprandial insulin concentrations in NO girls and increased fat oxidation in both OW and NO girls. The higher postintervention energy and CHO intake in the OW compared with the NO girls or differences in metabolism between the two groups may have compromised potential exercise-induced reductions in insulin the OW girls.

High intensity interval exercise is an effective alternative to moderate intensity exercise for improving glucose tolerance and insulin sensitivity in adolescent boys

“…7 Furthermore, undertaking aerobic exercise (500 kcal) ∼16 h before a high glycaemic index meal lowered postprandial plasma [insulin] but not [glucose] in normal weight girls. 19 Our findings extend this limited body of work by showing that improvements in glucose tolerance and IS can be achieved after just ∼28 min of MIE (∼180 kcal) or just 8 min of HIIE (22.8 min including recovery) in adolescent boys, and that these beneficial effects are exercise intensity-independent. Furthermore, our data cohere well with a recent study in pre-diabetic adults, where a single bout of highintensity exercise and an isoenergetic bout of MIE (∼180 kcal) had a beneficial effect on IS and glucose tolerance following an OGTT.…”

Exercise intensity and postprandial health outcomes in adolescents

“…This is of importance given the relationship between elevated resting fat oxidation and exercise-induced fat loss (Barwell et al 2009). Similar changes in resting fat oxidation have been reported 24 h after a single bout of HIIE in overweight and obese men (Whyte et al 2012), and it has been shown that ~2 MJ of exercise at an intensity corresponding to peak fat oxidation (~63% ̇O 2 peak ) increases postprandial fat oxidation in normal weight 12 y old girls on the subsequent day (Zakrzewski and Tolfrey 2012). Given the greater increase in postprandial fat oxidation following HIIE in the current study, exercise intensity appears to be an important mediator of this response and offers a low volume alternative to MIE.…”

A single exercise session increases insulin sensitivity in normal weight and overweight/obese adolescents

“…The current study extends the results from a subset of participants that we previously reported . There is now general agreement that a single exercise session completed up to 24 hours before a carbohydrate‐containing meal results in reduced glycemic and/or insulin excursion in adolescents . Cockcroft et al reported that this effect was independent of exercise intensity.…”

“…The improvement in insulin sensitivity was observed during oral glucose tolerance tests performed 10 to 40 minutes after exercise and persisted at 24 hours, but not 48 hours after exercise . Zackrzewski and Tolfrey did not measure the acute effect of exercise, but found that fasting insulin and fat oxidation were lower in NW, but not OW girls during a high‐glycemic index meal consumed ~15 hours after the exercise was completed. MacEneaney et al also examined the effects of prior day exercise in adolescents but measured responses to a high‐fat meal.…”

“…3 In contrast, when NW and overweight girls performed a single aerobic exercise session, the NW group had reduced fasting insulin and maintained higher fat oxidation the following morning, but these effects were not observed in the overweight group. 10 The latter results raise the possibility that the beneficial effects of exercise on insulin action and fuel metabolism in overweight youth might be blunted or more transient at the beginning of an exercise program.…”