Responses of Obese and Lean Girls Exercising under Heat and Thermoneutral Conditions

IUGR with infantile overnutrition programs an insulin-resistant phenotype through DNA methylation of peroxisome proliferator–activated receptor-γ coactivator-1α in rats

“…In fact, the association between body weight and body thermoregulation remains contestable. For example, before exercise, body temperature was higher in obese children (35), while another study found, in contrast, that obesity-prone dogs have lower core temperature than obesity-resistant dogs (36). In our study, the spontaneous physical activity also did not differ between the control and obese CG-IUGR rats; similarly, the diet-induced obese rat and the diet-resistant rat had no difference in spontaneous physical activity (37).…”

Novos horizontes para a normalização da aptidão cardiorrespiratória em crianças: Quebrando o paradigma

“…kg body mass -1. min -1 ) is broadly used in literature, is this the best way to compare and identify the effects of biological maturation, growth, and sex on aerobic fitness in children and adolescents? The traditional method to normalize aerobic fitness has been found to be inefficient and may lead to misinterpretations when physiological variables between groups of individuals with different body sizes and composition are compared [3][4][5][6]8,9 . Currently, there are alternatives that seem to be more appropriate to avoid the confounding effects of body size and body composition on performance variables 10 .…”

“…Some studies have used muscle volume (MV), free fat mass (FFM), total muscle mass or lower limb muscle mass as normalizing variables in the attempt to adjust for differences in body dimensions 6,8,11,12 . These variables were chosen to reflect the reality that under maximal intensity exercise, 90% of blood flow and VO 2 are allocated to ATP synthesis during muscle contraction.…”

“…Exercise physiologists are faced with the challenge of determining whether changes in physiological performance variables, such as VO 2max , are more related to normal growth and development or can be significantly altered by changes in physical activity levels. Indeed, such comparisons between groups or individuals' performance and their peers have been confounded by the body size effect [3][4][5][6] . A recent study published in the Brazilian Journal of Kinantropometry and Human Performance determined the influence of sexual maturation and physical activity level on cardiorespiratory fitness of schoolchildren of both sexes aged 9-14 years 7 .…”

“…With ratio standard analysis, it is assumed that VO 2max is normalized for body mass effects. However, VO 2max is often overestimated in individuals with low body mass and underestimated in those with high body mass 4,6,9 . The main reason for this is because oxygen consumption increases at a slower rate than body mass 3,4 .…”