Nutritional compensation to exercise- vs. diet-induced acute energy deficit in adolescents with obesity

Impact of physical activity on caloric and macronutrient intake in children and adolescents: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Physical activity is widely promoted to maintain and improve health across all ages. Investigating how physical activity affects subsequent food intake provides insight into the factors that contribute to maintaining energy balance and effective weight management.

OBJECTIVE

This systematic review and meta-analysis summarizes the evidence on the effect of acute physical activity on subsequent food intake in children and adolescents.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (PRISMA) were applied. Randomized controlled trials (RCTs) objectively measuring post-exercise energy intake in children and adolescents aged 5 to 18 years were included. Studies with self-reported food intake were excluded. The databases PubMed, Web of Science and Cochrane Library were searched for RCTs, and the data were summarized at a qualitative and quantitative level. Version 2 of the Cochrane risk-of-bias tool for randomized trials was used to assess risk of bias. Changes in energy intake were examined with random effects meta-analysis. (PROSPERO: CRD42022324259).

RESULTS

Out of 9582 studies, 22 RCTs with cross-over design remained eligible for meta-analysis. The primary outcome was post-intervention energy intake up to the next 24 h. Heterogeneity of studies was moderate, with an I2 of 57%. The median (interquartile range, IQR) energy expended while exercising was 240 (158) kcal. Meta-analysis of 41 study arms (exercise n = 780 and control n = 478) showed no differences in total energy intake between the exercise and control group with a mean difference MD = 23.31 [-27.54, 74.15] kcal. No subgroup differences were found. Macronutrient intake and appetite sensations where not substantially affected.

CONCLUSION

Engaging in exercise is a suitable means of raising activity-induced energy expenditure, without causing any noticeable changes in food intake or hunger within a single day.

Changes in ghrelin, GLP-1, and PYY levels after diet and exercise in obese individuals

OBJECTIVE

Diet and exercise, which are the building blocks of obesity management, provide weight loss by creating a negative energy balance. However, the effect of energy deficit induced by long-term diet and exercise on appetite hormones remains unclear. The study was designed to determine the effect of a 12-week diet and exercise program applied to obese individuals on the levels of appetite hormones, namely, ghrelin, GLP-1, and PYY.

METHODS

A total of 62 obese individuals (BMI≥30) and 48 healthy controls (BMI 18.50-29.99) participated in the study. Appropriate diet (1000-1500 kcal/day) and exercise (at least 5000 steps/day) programs were applied to obese individuals according to age, gender, and BMI. The ghrelin, GLP-1, and PYY values of the participants were analyzed by the ELISA method and commercial kit by taking venous blood samples before and after 12 weeks of treatment.

RESULTS

While ghrelin levels of individuals decreased significantly after diet and exercise, PYY levels increased significantly. However, despite the treatment applied, the GLP-1 and PYY levels of the case group did not reach the levels of the control group.

CONCLUSION

Long-term diet and exercise intervention had a positive effect on appetite regulation hormones. It reduced ghrelin levels after treatment. Associated weight loss was facilitated. In the case group, increased satiety hormones after combined treatment supported the maintenance of body weight by increasing satiety.

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.

Dietary Intervention on Overweight and Obesity after Confinement by COVID-19

BACKGROUND

Obesity has become a public health problem in our society and is associated with many diseases, including type 2 diabetes mellitus, cardiovascular diseases, dyslipidemia, respiratory diseases, and cancer. Several studies relate weight loss in obese patients to improved anthropometric measurements and cardiometabolic risk. The objective of our study was to evaluate anthropometric changes, analytical parameters, insulin resistance, fatty liver, and metabolic scales, after a personalized weight loss program, through dietary advice to increase adherence to the Mediterranean diet and a motivational booster via mobile SMS messaging.

METHODS

Intervention study on a sample of 1964 workers, in which different anthropometric parameters were evaluated before and after dietary intervention: the metabolic score of insulin resistance; non-alcoholic fatty liver disease using different scales; metabolic syndrome; atherogenic dyslipidemia; and the cardiometabolic index. A descriptive analysis of the categorical variables was performed, by calculating the frequency and distribution of the responses for each one. For quantitative variables, the mean and standard deviation were calculated, since they followed a normal distribution. Bivariate association analysis was performed by applying the chi-squared test (corrected by Fisher's exact statistic when conditions required it) and Student's t-test for independent samples (for comparison of means).

RESULTS

The population subjected to the Mediterranean diet improved in all the variables evaluated at 12 months of follow-up and compliance with the diet.

CONCLUSIONS

Dietary advice on a Mediterranean diet and its reinforcement with reminder messages through the use of mobile phones may be useful to improve the parameters evaluated in this study and reduce the cardiometabolic risk of patients.

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% VO_2peak 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% VO_2peak 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.

Diet- but not exercise-induced iso-energetic deficit induces compensatory appetitive responses

Although physical exercise and dietary restriction can be both used to induce energy deficits, they have been suggested to favor different compensatory appetitive responses. While dietary restriction might favor increased subsequent energy intake and appetite sensations, such compensatory responses have not been observed after a similar deficit by exercise. The present work provides a first overview of the actual evidences discussing the effects of iso-energetic deficits induced by exercise versus dietary restriction on subsequent energy intake, appetite sensations, and on the potentially involved hedonic and physiological mechanisms.

Delayed meal timing after exercise is associated with reduced appetite and energy intake in adolescents with obesity

BACKGROUND

While the beneficial effects of exercise on appetite might depend on its timing during the day or relative to a meal, this remains poorly explored in youth.

OBJECTIVES

To examine the importance of meal timing (+30 vs +90 minutes) after performing exercise on energy intake, appetite and food reward in adolescents with obesity.

METHODS

Eighteen adolescents with obesity randomly completed three conditions: (a) lunch (12:00 pm) set 30 minutes after a rest session (11:00 am); (b) lunch (12:00 pm) set 30 minutes after an exercise session (11:00 am)(MEAL-30); (c) lunch (01:00 pm) set 90 minutes after an exercise session (11:00 am)(MEAL-90). Lunch and dinner ad libitum energy intake was assessed, food reward (LFPQ) assessed before and after lunch, and before dinner, appetite sensations were assessed at regular intervals.

RESULTS

Energy intake was lower at MEAL-90 than MEAL-30 and CON at lunch (P < .05 and P < .01, respectively) and lunch + dinner combined (P < .001). A decrease in intake (g) of protein, fat and carbohydrate was observed. Post-exercise hunger was lower on MEAL-90 compared with CON. No condition effects were found at lunch for food reward.

CONCLUSIONS

Delaying the timing of the meal after exercise might help affect energy balance by decreasing ad libitum energy intake without increasing hunger and by improving satiety in adolescents with obesity.

The Effects of the Type of Exercise and Physical Activity on Eating Behavior and Body Composition in Overweight and Obese Subjects

The aim of this study was to examine whether a type of exercise favors better compliance with a prescribed diet, higher eating-related motivation, healthier diet composition or greater changes in body composition in overweight and obese subjects. One hundred and sixty-two (males n = 79), aged 18-50 years, were randomized into four intervention groups during 24 weeks: strength, endurance, combined strength + endurance and guideline-based physical activity; all in combination with a 25-30% caloric restriction diet. A food frequency questionnaire and a "3-day food and drink record" were applied pre- and post-intervention. Diet and exercise-related motivation levels were evaluated with a questionnaire developed for this study. Body composition was assessed by DXA and habitual physical activity was measured by accelerometry. Body weight, body mass index (BMI) and body fat percentage decreased and lean body mass increased after the intervention, without differences by groups. No interactions were observed between intervention groups and time; all showing a decreased in energy intake (p < 0.001). Carbohydrate and protein intakes increased, and fat intake decreased from pre- to post-intervention without significant interactions with intervention groups, BMI category or gender (p < 0.001). Diet-related motivation showed a tendency to increase from pre- to post-intervention (70.0 ± 0.5 vs 71.0 ± 0.6, p = 0.053), without significant interactions with intervention groups, BMI or gender. Regarding motivation for exercise, gender x time interactions were observed (F(1,146) = 7.452, p = 0.007): Women increased their motivation after the intervention (pre: 17.6 ± 0.3, post: 18.2 ± 0.3), while men maintained it. These findings suggest that there are no substantial effects of exercise type on energy intake, macronutrient selection or body composition changes. After a six-month weight loss program, individuals did not reduce their motivation related to diet or exercise, especially women. Individuals who initiate a long-term exercise program do not increase their energy intake in a compensatory fashion, if diet advices are included.

Post-moderate-intensity exercise energy replacement does not reduce subsequent appetite and energy intake in adolescents with obesity

Exercise modifies energy intake (EI) in adolescents with obesity, but whether this is mediated by the exercise-induced energy deficit remains unknown. The present study examined the effect of exercise with and without dietary replacement of the exercise energy expenditure on appetite, EI and food reward in adolescents with obesity. Fourteen 12–15-year-old adolescents with obesity (eight girls; Tanner 3–4; BMI 34·8 (sd 5·7) kg/m2; BMI z score 2·3 (sd 0·4)) randomly completed three experimental conditions: (i) rest control (CON); (ii) 30-min cycling (EX) and (iii) 30-min cycling with dietary energy replacement (EX + R). Ad libitum EI was assessed at lunch and dinner, and food reward (Leeds Food Preference Questionnaire) before and after lunch. Appetite was assessed at regular intervals. Lunch, evening and total EI (excluding the post-exercise snack in EX − R) were similar across conditions. Lunch and total EI including the post-exercise snack in EX + R were higher in EX − R than CON and EX; EX and CON were similar. Total relative EI was lower in EX (6284 (sd 2042) kJ) compared with CON (7167 (sd 2218) kJ; P < 0·05) and higher in EX + R (7736 (sd 2033) kJ) compared with CON (P < 0·001). Appetite and satiety quotients did not differ across conditions (P ≥ 0·10). Pre-meal explicit liking for fat was lower in EX compared with CON and EX + R (P = 0·05). There was time by condition interaction between EX and CON for explicit wanting and liking for fat (P = 0·01). Despite similar appetite and EI, adolescents with obesity do not adapt their post-exercise food intake to account for immediate dietary replacement of the exercise-induced energy deficit, favouring a short-term positive energy balance.

Effects of high-intensity interval training and nutrition advice on cardiometabolic markers and aerobic fitness in adolescent girls with obesity

The aim of the study was to compare the effects of high-intensity interval training (HIIT) and nutrition advice on cardiometabolic biomarkers, hormonal parameters, and cardiorespiratory fitness in adolescent girls with obesity. Adolescent girls with obesity (n = 44, aged 13-19 years) were randomized into a 12-week intervention as follows: (i) dietary advice and HIIT (n = 22), and (ii) dietary advice only (n = 22). The concentration of biomarkers of inflammation, biochemical and hormonal testing, oral glucose tolerance test, cardiorespiratory fitness, physical activity levels, and nutrition were assessed. After a 3-month intervention, the diet+HIIT group significantly increased insulin sensitivity index (-0.34 ± 1.52 vs. 1.05 ± 3.21; p = 0.001) and work load (0.6 ± 11.3 W vs. 14.6 ± 20.2 W; p = 0.024) and decreased glucose area under the curve (-0.29 ± 4.69 vs. -0.98 ± 4.06; p = 0.040), insulin area under the curve (-9.65 ± 117.9 vs. -98.7 ± 201.8; p = 0.003), and high-sensitivity C-reactive protein (hs-CRP) (0.12 ± 1.92 mg/L vs. -1.47 ± 3.67 mg/L; p = 0.039) in comparison with the diet group. Regarding within-group changes, both groups had significant improvements in body mass index (BMI), BMI-standard deviation score, body fat percentage, and systolic blood pressure. Positive impact on waist circumference, waist circumference/height ratio, diastolic blood pressure, hs-CRP, work load, maximal heart rate, and resting heart rate was observed only after the diet+HIIT intervention. No significant change was noted in peak oxygen uptake, lipid profile, and hormonal parameters between groups after intervention. Novelty HIIT and nutrition advice increased insulin sensitivity and decreased BMI, body fat, systolic blood pressure, and diastolic blood pressure. Nutrition advice decreased BMI, body fat, and systolic blood pressure in adolescent girls with obesity.

Energy depletion by 24-h fast leads to compensatory appetite responses compared with matched energy depletion by exercise in healthy young males

Although there is a growing interest for the effects of intermittent fasting on energy balance, this study aimed to compare appetite, energy intake and food reward responses with an energy depletion induced either by 24-h food restriction or an equivalent deficit with exercise in healthy males. In all, twelve healthy lean males (21·5 (sd 0·5) years old; BMI: 22·5 (sd 1·7) kg/m2) participated in this study. Body composition, aerobic capacity, food preferences and energy intake were assessed. They randomly completed three conditions: (i) no depletion (CON); (ii) full 24-h energy restrictions (Def-EI); and (iii) exercise condition (Def-EX). Ad libitum energy intake and food reward were assessed at the end of each session. Appetite feelings were assessed regularly. Ad libitum energy intake was higher on Def-EI (7330 (sd 2975) kJ (1752 (sd 711) kcal) compared with that on CON (5301 (sd 1205) kJ (1267 (sd 288) kcal)) (P<0·05), with no difference between CON and Def-EX (6238 (sd 1741) kJ (1491 (sd 416) kcal) (P=0·38) and between Def-EX and Def-EI (P=0·22). There was no difference in the percent energy ingested from macronutrients. Hunger was lower on CON and Def-EX compared with Def-EI (P<0·001). Satiety was higher on CON and Def-EI compared with that on Def-EX (P<0·001). There was a significant interaction condition × time for food choice fat bias (P=0·04), showing a greater preference for high-fat v. low-fat food during Def-EI and Def-EX. Although 24-h fasting leads to increased energy intake at the following test meal (without total daily energy intake difference), increased hunger profile and decreased post-meal food choice fat bias, such nutritional responses are not observed after a similar deficit induced by exercise.

Public views of different sources of health advice: pharmacists, social media and mobile health applications

OBJECTIVES

Investigating public perceptions of community pharmacists (CP) in public health and their use of social media (SM) and mobile health applications (MH apps) in that regard.

METHODS

Two surveys were created. One sought public perceptions of SM and the other of MH apps for health advice. Both included a section on perceptions of the role of CPs in public health. A convenience sampling strategy, based on proximity, was used.The study population was the public (n = 8 500 000) living in Greater London. The general public were recruited face-to-face in public spaces. A minimum sample (95% confidence interval/5% margin of error) of 385 was needed. Ethical approval was obtained from the university ethics committee. Responses were analysed in SPSS.

KEY FINDINGS

About 820/1800 (45.6%) completed one/both surveys. Respondents seek health advice primarily from GPs, followed by digital mediums and then CPs. Under 35s use digital mediums more frequently (P = 0.039). Those who had used SM (41.7%) or MH apps (61.8%) for health information did not confirm its accuracy with a healthcare professional (HCP). Of those that did (MH apps = 39.2%; SM = 58.3%), the HCP disagreed with the information on MH apps and SM on 19.6% and 36.7% of occasions, respectively. Nevertheless, 64.5% stated that if a SM page was maintained by an HCP they would use it.

CONCLUSIONS

The public are using digital mediums for health advice instead of speaking to an HCP. If CPs want to have an impact on public health they must start imbedding digital mediums into their services.

Mechanisms responsible for homeostatic appetite control: theoretical advances and practical implications

Homeostatic appetite control is part of a psychobiological system that has evolved to maintain an adequate supply of nutrients for growth and maintenance. The system links the physiological needs for energy with the behaviour that satisfies these needs (feeding), and is shaped by excitatory and inhibitory signals. Owing to rapid shifts in the food environment, homeostatic appetite control is not well adapted for modern-day human functioning. Areas covered: Homeostatic appetite control has two divisions. Tonic processes exert stable and enduring influences, with signals arising from bodily tissues and metabolism. Episodic processes fluctuate rapidly and are related to nutrient ingestion and the composition of foods consumed. Research in these areas incorporates potent endocrine signals that can influence behaviour. Expert commentary: The regulation of adipose tissue, and its impact on appetite (energy) homeostasis, has been heavily researched. More recently however, it has been demonstrated that fat-free mass has the potential to act as a tonic driver of food intake. A challenging issue is to determine how the post-prandial action of episodic satiety hormones and gastrointestinal mechanisms can effectively brake the metabolic drive to eat, in order to keep food intake under control and prevent a positive energy balance and fat accumulation.