Higher energy flux may improve short-term appetite control in adolescents with obesity: the NEXT study.

Recent evidence suggests better appetite control in states of high-energy flux (HEF) in adults and lean children. Nevertheless, it is unknown whether this extends to youth with obesity. This study compares the effects of low, moderate or HEF on short-term appetitive control in adolescents with obesity. Sixteen adolescents with obesity (12-16 years, Tanner stages 3-5, 11 females) randomly completed three conditions: (i) low-energy flux (LEF); (ii) moderate energy flux (MEF; + 250 kcal) and (iii) HEF (HEF; + 500 kcal). Energy flux was achieved in MEF and HEF through elevated energy intake (EI) and concomitant increase in energy expenditure using cycling exercise (65 % VO2peak). Ad libitum EI, macronutrient intake and relative EI were assessed at dinner, subjective appetite sensations taken at regular intervals and food reward measured before dinner. Ad libitum EI at dinner was greater in LEF compared with HEF (P = 0·008), and relative EI (REI) was higher in LEF compared with MEF (P = 0·003) and HEF (P < 0·001). The absolute consumption of carbohydrates was lower in LEF compared with MEF (P = 0·047) and HEF (P < 0·001). Total AUC for hunger and desire to eat was lower in HEF compared with LEF (P < 0·001) and MEF (P = 0·038). Total AUC for prospective food consumption was lower on HEF compared with LEF (P = 0·004). Food choice sweet bias was higher in HEF (P = 0·005) compared with LEF. To conclude, increasing energy flux may improve short-term appetite control in adolescents with obesity.

The energy content of meals with a similar macronutrient distribution may have a greater impact on appetite sensations than food preferences in adolescents with obesity: A secondary analysis.

PURPOSE: The energy and macronutrient composition of a meal has been shown to influence postprandial appetitive responses, but it is not clear how energy content independent of macronutrient distribution affects postprandial appetite in adolescents with obesity. Extracting data from a primary study testing the effect of energy turnover on appetite, this secondary analysis assessed how fixed meals varying in energy content with similar macronutrient distributions influences postprandial appetite sensations and food reward. METHODS: Using a randomised, counterbalanced crossover design, N = 14 adolescents with obesity (Mage = 12.71, SDage = 0.99; 10 female) consumed fixed lunch meals with similar macronutrient content starting at 750 kcal in energy and progressively increasing by 250 kcal on three different test days. Liking and wanting for food images varying in fat and taste were assessed at baseline and immediately after meal consumption. Appetite sensations were assessed in half-hour intervals from baseline to 1-h post-meal. RESULTS: The area under the curve for subjective hunger (p < .001, ω = 0.36), desire to eat (p < .001, ω = 0.54), and prospective food consumption (p = .004, ω = 0.32) were significantly lower after consumption of the higher calorie meals relative to the lowest. Explicit wanting for sweet foods increased after intake of the intermediate calorie meal yet decreased after the highest calorie meal (p = .014, ω = 0.09). Conversely, implicit wanting sweet bias increased after consumption of the test meal independent of energy content (p < .001, ω = 0.15). CONCLUSION: The consumption of additional calories without a meaningful change in macronutrient distribution may affect appetite sensations more reliably than hedonic responses to energy-dense foods in adolescents with obesity.

Weight loss does not affect the sit-to-stand metabolic cost in adolescents with obesity.

PURPOSE: There is considerable interest in simple and effective methods to reduce sitting time and increase energy expenditure, and standing breaks have emerged as a realisable approach in individuals with obesity. The aim of the present study was to determine the extent to which energy expenditure in standing differs from sitting, and whether this energetic and metabolic-related responses are modified following a weight loss program in adolescents with obesity. METHODS: After body composition assessment (DXA), cardiorespiratory and metabolic variables were continuously recorded (indirect calorimetry) during 10 min while sitting and then during 5 min standing posture before (n = 21; T1) and at the end of a multidisciplinary intervention (n = 17; T2) in adolescents with obesity. RESULTS: Before and after the intervention, energy expenditure and fat oxidation rates were significantly increased in standing compared with sitting. Weight loss did not change the relationship between sitting and standing energy expenditure. Sitting energy expenditure represented 1.0 and 1.1 Metabolic Equivalent of Task at T1 and T2, and increased to 1.1 and 1.2 during standing at T1 and T2, respectively. The percentage of change of android fat mass between T1 and T2 was positively associated with the percentage of change in energy expenditure from sitting to standing at T2. CONCLUSION: The vast majority of the adolescents with obesity significantly increased their energy expenditure between sitting and standing, both before and after a weight loss intervention. However, the standing posture did not allow breaking the sedentary threshold. Abdominal fat mass is associated with energic profile.

Changes in Sedentary Time and Implicit Preference for Sedentary Behaviors in Response to a One-Month Educational Intervention in Primary School Children: Results from the Globe Trotter Pilot Cluster-Randomized Study.

School-based multi-component educational interventions have been encouraged to improve children's movement behaviors. The present study evaluates the effect of the Globe Trotter Initiative on physical activity (PA) level, sedentary time, physical fitness and activity preferences in primary school children. A total of 361 children (9−10 years) participated in this cluster-randomized trial. Nine schools were randomized as control (CON, 121 children) or Globe Trotter schools (GT, 240 children). Physical fitness, body composition, anthropometric characteristics, PA level, sedentary behaviors, physical self-perception, and activity preferences were evaluated at baseline (T0) and after the one-month intervention (T1). Grip strength performance and overall completion time of the obstacle course show a significant time effect (p < 0.001) in both groups (no group effect). PA level and physical self-perception did not significantly show time nor group effects. The sedentary behavior score displays a significant "time × group" interaction effect (p = 0.04) with a significant reduction between T0 and T1 in the GT group only (p < 0.001). The explicit liking for sedentary activities shows a significant "time × group" interaction (p = 0.02) with a significant decrease between T0 and T1 in the GT group only (p < 0.001). The explicit wanting for sedentary activities show a significant "time × group" interaction (p = 0.02) with a significant decrease between T0 and T1 in the GT group only (p < 0.001). The short-term, multi-component, behavioral, educational GT intervention had beneficial effects on primary-school-aged children's sedentary time and implicit preference for physical over sedentary activities.

Dietary- but not exercise-induced acute iso-energetic deficit result in short-term appetitive compensatory responses in adolescents with obesity.

BACKGROUND: Producing negative energy balance rests on the creation of energy deficits that have been shown, depending on their modality, to induce potential appetitive compensatory responses. The aim of this study was to compare energy intake (EI), appetite feelings, and the hedonic responses to equivalent acute energy deficits induced by exercise versus energy restriction in adolescents with obesity. METHODS: In a within-participants design, seventeen adolescents with obesity (12-16 years, Tanner stage 3-5, 9 males) randomly completed three conditions: i) control (CON); ii) deficit induced by diet only (Def-EI); and iii) deficit induced by exercise only (Def-EX). Lunch was calibrated to generate a 400-kcal deficit in Def-EI and remained similar in CON and Def-EX. A 400-kcal deficit was created through a cycling bout set at 65% VO2peak in Def-EX. Ad libitum EI, macronutrient intake and relative EI (REI) were assessed at dinner, subjective appetite sensations taken at regular intervals, and food reward measured before dinner. RESULTS: Food intake at dinner was greater in Def-EI (1112 ± 265 kcal) compared to CON (983 ± 277 kcal; p = 0.005) and Def-EX (1009 ± 281 kcal; p = 0.025). Absolute protein and lipid intake were significantly higher in Def-EI (52.4 ± 9.5 g and 36.8 ± 8.9 g respectively) compared with both CON (44.9 ± 12.6 g; p = 0.001 and 33.8 ± 10.1 g; p = 0.002 respectively) and Def-EX (47.3 ± 11.8 g, p = 0.018, 35.4 ± 10.1 g, p = 0.036 respectively). Area under the curve (AUC) for hunger, desire to eat and prospective food consumption were significantly higher in Def-EI compared with both CON (p = 0.0001) and Def-EX (p = 0.0001). AUC for fullness was significantly lower on Def-EI compared with CON and Def-EX (p = 0.0001). Implicit wanting for sweet food was significantly lower on Def-EX (p = 0.031), relative to CON. CONCLUSION: Appetitive compensatory responses that are observed after iso-caloric energy restriction in adolescents with obesity are absent with acute exercise, which could contribute to optimize our impact on short-term energy balance.

Effect of acute dietary- versus combined dietary and exercise-induced energy deficits on subsequent energy intake, appetite and food reward in adolescents with obesity.

BACKGROUND: Acute dietary-induced energy deficits have been shown to favor compensatory appetitive responses. The aim of this study was to compare energy intake (EI), appetite sensations and the hedonic responses to equivalent energy deficits induced by dietary restriction alone and combined with exercise in adolescents with obesity. METHODS: In a within-subjects design, seventeen adolescents with obesity (12-16 years, Tanner stage 3-5, 6 males) randomly completed three 14 h conditions: (i) control (CON); (ii) deficit induced by diet only (Def-EI) and; (iii) deficit induced by combined diet and physical exercise (Def-mixed). Breakfast and lunch were calibrated to generate a 500 kcal deficit in Def-EI and 250 kcal deficit in Def-mixed. A 250 kcal deficit was created through a cycling exercise set at 65% VO2peak in Def-mixed. Ad libitum EI, macronutrients and relative EI (REI) were assessed at dinner, subjective appetite sensations taken at regular intervals, and food reward measured before dinner. RESULTS: EI at dinner was significantly lower in Def-EI compared to CON (p = 0.014; Effect size (ES): -0.59 [-1.07; -0.12]), with no difference between Def-mixed and both CON and Def-EI. Total REI was lower in both deficit conditions compared with CON (Def-mixed: p < 0.001; ES: -3.80 [-4.27; -3.32], Def-EI: p < 0.001; ES: -4.90 [-5.37; -4.42] respectively), indicating incomplete compensation for the energy deficits. Absolute protein ingestion at dinner was lower in Def-EI than Def-mixed (p = 0.037; ES: -0.50 [-0.98; -0.03]) and absolute lipid ingestion was lower in Def-EI than in CON (p = 0.033; ES: -0.51 [-0.99; -0.04]). A higher proportion of protein and a lower proportion of carbohydrates was observed in Def-mixed than in Def-EI (p = 0.078; ES: -0.42 [-0.90; 0.04] and p = 0.067; ES: 0.44 [-0.03; 0.92] respectively). Total area under the curve for appetite sensations were similar between conditions. Explicit liking for sweet relative to savoury food was lower in Def-mixed compared to CON (p = 0.027; ES: -0.53 [-1.01; -0.06]) with no difference in food reward between Def-EI and CON. CONCLUSION: Neither of the two acute isoenergetic deficits led to subsequent appetitive compensation, with the dietary deficit even inducing a lower ad libitum EI at the subsequent dinner. Further studies are needed to better understand the appetitive response to dietary and exercise energy balance manipulations in this population.

Adverse Collateral Effects of COVID-19 Public Health Restrictions on Physical Fitness and Cognitive Performance in Primary School Children.

The aim of the present study was to evaluate whether the COVID-19-related confinement and social restrictions affected the levels of physical fitness and academic achievement in primary school French children. A total of 206 primary school children (106 before confinements and 100 after restrictions) completed a test battery evaluating their anthropometric characteristics, body compositions, activity preferences, cognitive performances and physical fitness. The performance of the Standing Long Jump was better at T0 (169.9 ± 142.5 cm) compared to T1 (135.2 ± 31.4 cm) (p = 0.0367), and the Medicine Ball Throw performance declined from T0 to T1 (297.3 ± 81.1 cm vs. 249 ± 52 cm; p < 0.0001). Motor skills (26.9 ± 6.2 s vs. 30.9 ± 5.4 s; p < 0.0001), the shuttle-run test (stages completed), Maximal Aerobic Speed, and the estimated VO2max were lower at T1 compared to T0 (p < 0.0001). Executive functioning was found to be greater at T0 compared to T1 (p < 0.0001). Explicit liking or wanting for sedentary or physical activities did not change between T0 and T1. Both overall physical fitness and cognitive performance drastically declined among primary school French children with the COVID-19-related public health restrictions, which reinforces the need to urgently develop preventive strategies in anticipation of further mitigation measures.