Energy Intake Over Two Days is Unaffected by Acute Spring Interval Exercise Despite Increased Appetite and Energy Expenditure

A cumulative effect of increased post-exercise oxygen consumption (V̇O2), lipid oxidation and/or reduced energy intake (EI) may explain the fat loss associated with sprint interval exercise (SIE) training. The purpose of this study was to assess the effects of SIE on EI, appetite ratings and peptides, V̇O2, and substrate oxidation (RER). Eight men completed 2 treatments, consisting of consecutive 10-h trials: SIE/recovery (SIEx), and no exercise control (NoEx). Immediate post-exercise suppression of appetite and increase in peptide YY were observed during SIEx. Despite this, overall treatment appetite was greater with SIEx but this did not affect total EI. RER was lower ~6 h post-exercise and total V̇O2 was greater during SIEx vs NoEx. Compared with no exercise control, SIE increases daily energy expenditure but energy intake is unaffected at least acutely. SIE-induced increases in both energy expenditure and lipid oxidation may explain the fat loss associated with this training modality

The influence of physical activity level on the sensitivity of the appetite control system

Background: Based on the non-linear relationship between energy intake and physical activity level demonstrated by Mayer et al. (1956), it has been proposed that there is a dysregulation of appetite at lower levels of physical activity leading to overconsumption, whereas at higher levels of physical activity, appetite control is more sensitive. However, the mechanisms underlying this relationship are not well understood. Objective: This thesis aimed to shed light on the impact of habitual physical activity level in lean individuals and exercise training in individuals with overweight and obesity on homeostatic (physiological) and non-homeostatic (hedonic and eating behaviour traits) appetite processes, including those that initiate and terminate feeding (satiation) and suppress inter-meal hunger (satiety), as well as passive overconsumption (unintentional increase in energy intake with high-energy-density/high-fat foods). Methods: A systematic review was conducted, followed by four experimental studies. The studies employed a multi-level experimental platform that included biological, behavioural and psychological aspects of energy balance including free-living physical activity, food intake, diet composition, food reward (liking and wanting), body composition, energy expenditure and fasting appetite-related peptides. Results: The systematic review revealed a J-shaped relationship between physical activity level and energy intake, corroborating previous findings. Data from the experimental studies indicated that in lean individuals, physical activity did not influence satiation at meals varying in dietary fat content, but moderate to high active individuals showed enhanced satiety with better ability to adjust intake following preloads varying in energy content. Exercise training (12 weeks) in inactive individuals with overweight and obesity improved both homeostatic and non-homeostatic appetite control, which may be mediated by exercise-induced fat loss. Across all studies, physical activity was associated with lower body fat and greater daily energy expenditure, and energy density was positively associated with energy intake and passive overconsumption. Conclusions: This thesis provides confirmatory evidence that physical activity impacts appetite control through a dual-process action expressed through an increased drive to eat from greater energy expenditure, together with enhanced satiety response to food in both lean and overweight/obese individuals. These processes may allow for more accurate matching of energy intake to requirements and a reduction in the risk of overconsumption at higher levels of physical activity

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

Introduction: 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

Measuring food preference and reward: application and cross-cultural adaptation of the leeds food preference questionnaire in human experimental research

Decisions about what we eat play a central role in human appetite and energy balance. Measuring food reward and its underlying components of implicit motivation (wanting) and explicit sensory pleasure (liking) is therefore important in understanding which foods are preferred in a given context and at a given moment in time. Among the different methods used to measure food reward, the Leeds Food Preference Questionnaire (LFPQ) is a well-established tool that has been widely used in the scientific field for over 10 years. The original LFPQ measures explicit liking and implicit wanting for the same visual food stimuli varying along two nutritional dimensions: fat (high or low) and taste (sweet or savoury/non-sweet). With increasing use of the LFPQ (in original or adapted forms) across different cultural and scientific contexts, there is a need for a set of recommendations for effective execution as well as cultural and nutritional adaptations of the tool. This paper aims to describe the current status of the LFPQ for researchers new to the methodology, and to provide standards of good practice that can be adopted for its cultural adaptation and use in the laboratory or clinic. This paper details procedures for the creation and validation of appropriate food stimuli; implementation of the tool for sensitive measures of food reward; and interpretation of the main end-points of the LFPQ. Following these steps will facilitate comparisons of findings between studies and lead to a better understanding of the role of food reward in human eating behaviour

Effect of a 10-month residential multidisciplinary weight loss intervention on food reward in adolescents with obesity

Background While multidisciplinary weight loss (WL) programs have been suggested to improve the sensitivity of appetite control system, this study examined for the first time the effect of a specific multidisciplinary intervention on the hedonic aspects of food intake in adolescents with obesity. Study Design Twenty-four adolescents (11–15 years) with obesity (mean BMI: 35.7 ± 4.5 kg/m2; BMI percentile: 98.7 ± 0.5) took part in a 10-month inpatient WL program, which included physical activity, nutritional education and psychological support. Height, weight, body composition, food reward (pre- and post-meal), ad libitum energy intake, appetite sensations and eating behavior traits were assessed at baseline, 5 months and at the end of the 10-month intervention. Analyses were conducted with linear mixed models and paired t-tests. Results The mean WL was 8.9 ± 6.9 kg. Appetite sensations and pre-meal hedonic ratings of liking for all food categories (HF: high-fat; LF: low-fat; SA: savory; SW: sweet) increased after 5 months (fasting hunger, p = 0.02; fasting desire to eat, p = 0.01; daily hunger, p = 0.001; pre-meal liking for HFSA, p = 0.03; LFSA, p = 0.04; HFSW, p = 0.009; LFSW, p = 0.005). In contrast, appetite sensations (fasting and daily), emotional eating (p < 0.001), uncontrolled eating (p = 0.009), and pre-meal explicit liking (for all food categories) decreased between months 5 and 10. Post-meal liking for HFSA (p < 0.001), LFSA (p = 0.002), HFSW (p = 0.02) and LFSW (p < 0.001) decreased between baseline and month 5 and remained unchanged between months 5 and 10. Conclusion These findings suggest that adaptive mechanisms to WL occurring in the short-to-medium term are attenuated in the longer term with the persistence of WL. These results indicate improvements in the reward response to food in adolescents with obesity and may contribute to the beneficial effect of multicomponent WL interventions in this population. Future studies are required to confirm these findings and elucidate underlying mechanisms

Impact of physical activity level and dietary fat content on passive overconsumption of energy in non-obese adults

Background: Passive overconsumption is the increase in energy intake driven by the high-fat energy-dense food environment. This can be explained in part because dietary fat has a weaker effect on satiation (i.e. process that terminates feeding). Habitually active individuals show improved satiety (i.e. process involved in post-meal suppression of hunger) but any improvement in satiation is unknown. Here we examined whether habitual physical activity mitigates passive overconsumption through enhanced satiation in response to a high-fat meal. Methods: Twenty-one non-obese individuals with high levels of physical activity (HiPA) and 19 individuals with low levels of physical activity (LoPA) matched for body mass index (mean = 22.8 kg/m2) were recruited. Passive overconsumption was assessed by comparing ad libitum energy intake from covertly manipulated high-fat (HFAT; 50% fat) or high-carbohydrate (HCHO; 70% carbohydrate) meals in a randomized crossover design. Habitual physical activity was assessed using SenseWear accelerometers (SWA). Body composition, resting metabolic rate, eating behaviour traits, fasting appetite-related peptides and hedonic food reward were also measured. Results: In the whole sample, passive overconsumption was observed with greater energy intake at HFAT compared to HCHO (p  0.05). SWA confirmed that HiPA were more active than LoPA (p  0.05 for all). Conclusions: Non-obese individuals with high or low physical activity levels but matched for BMI showed similar susceptibility to passive overconsumption when consuming an ad libitum high-fat compared to a high-carbohydrate meal. This occurred despite increased total daily energy expenditure and improved body composition in HiPA. Greater differences in body composition and/or physical activity levels may be required to impact on satiation

Appetite Control across the Lifecourse: The Acute Impact of Breakfast Drink Quantity and Protein Content. The Full4Health Project

Understanding the mechanisms of hunger, satiety and how nutrients affect appetite control is important for successful weight management across the lifecourse. The primary aim of this study was to describe acute appetite control across the lifecourse, comparing age groups (children, adolescents, adults, elderly), weight categories, genders and European sites (Scotland and Greece). Participants (n = 391) consumed four test drinks, varying in composition (15% (normal protein, NP) and 30% (high protein, HP) of energy from protein) and quantity (based on 100% basal metabolic rate (BMR) and 140% BMR), on four separate days in a double-blind randomized controlled study. Ad libitum energy intake (EI), subjective appetite and biomarkers of appetite and metabolism (adults and elderly only) were measured. The adults’ appetite was significantly greater than that of the elderly across all drink types (p 0.004) and in response to drink quantities (p 0.001). There were no significant differences in EI between age groups, weight categories, genders or sites. Concentrations of glucagon-like peptide 1 (GLP-1) and peptide YY (PYY) were significantly greater in the elderly than the adults (p 0.001). Ghrelin and fasting leptin concentrations differed significantly between weight categories, genders and sites (p 0.05), while GLP-1 and PYY concentrations differed significantly between genders only (p 0.05). Compared to NP drinks, HP drinks significantly increased postprandial GLP-1 and PYY (p 0.001). Advanced age was concomitant with reduced appetite and elevated anorectic hormone release, which may contribute to the development of malnutrition. In addition, appetite hormone concentrations differed between weight categories, genders and geographical locations

Acute and two-week effects of Neotame, Stevia Rebaudioside M and sucrose-sweetened biscuits on postprandial appetite and endocrine response in adults with overweight/obesity – a randomised crossover trial from the SWEET Consortium.

BackgroundSweeteners and sweetness enhancers (S&SE) are used to replace energy yielding sugars and maintain sweet taste in a wide range of products, but controversy exists about their effects on appetite and endocrine responses in reduced or no added sugar solid foods. The aim of the current study was to evaluate the acute (1 day) and repeated (two-week daily) ingestive effects of 2 S&SE vs. sucrose formulations of biscuit with fruit filling on appetite and endocrine responses in adults with overweight and obesity.MethodsIn a randomised crossover trial, 53 healthy adults (33 female, 20 male) with overweight/obesity in England and France consumed biscuits with fruit filling containing 1) sucrose, or reformulated with either 2) Stevia Rebaudioside M (StRebM) or 3) Neotame daily during three, two-week intervention periods with a two-week washout. The primary outcome was composite appetite score defined as [desire to eat + hunger + (100 - fullness) + prospective consumption]/4.FindingsEach formulation elicited a similar reduction in appetite sensations (3-h postprandial net iAUC). Postprandial insulin (2-h iAUC) was lower after Neotame (95% CI (0.093, 0.166); p InterpretationIn conclusion, biscuits reformulated to replace sugar using StRebM or Neotame showed no differences in appetite or endocrine responses, acutely or after a two-week exposure, but can reduce postprandial insulin and glucose response in adults with overweight or obesity.FundingThe present study was funded by the Horizon 2020 program: Sweeteners and sweetness enhancers: Impact on health, obesity, safety and sustainability (acronym: SWEET, grant no: 774293)

Does Habitual Physical Activity Increase the Sensitivity of the Appetite Control System? A Systematic Review.

BACKGROUND: It has been proposed that habitual physical activity improves appetite control; however, the evidence has never been systematically reviewed. OBJECTIVE: To examine whether appetite control (e.g. subjective appetite, appetite-related peptides, food intake) differs according to levels of physical activity. DATA SOURCES: Medline, Embase and SPORTDiscus were searched for articles published between 1996 and 2015, using keywords pertaining to physical activity, appetite, food intake and appetite-related peptides. STUDY SELECTION: Articles were included if they involved healthy non-smoking adults (aged 18-64 years) participating in cross-sectional studies examining appetite control in active and inactive individuals; or before and after exercise training in previously inactive individuals. STUDY APPRAISAL AND SYNTHESIS: Of 77 full-text articles assessed, 28 studies (14 cross-sectional; 14 exercise training) met the inclusion criteria. RESULTS: Appetite sensations and absolute energy intake did not differ consistently across studies. Active individuals had a greater ability to compensate for high-energy preloads through reductions in energy intake, in comparison with inactive controls. When physical activity level was graded across cross-sectional studies (low, medium, high, very high), a significant curvilinear effect on energy intake (z-scores) was observed. LIMITATIONS: Methodological issues existed concerning the small number of studies, lack of objective quantification of food intake, and various definitions used to define active and inactive individuals. CONCLUSION: Habitually active individuals showed improved compensation for the energy density of foods, but no consistent differences in appetite or absolute energy intake, in comparison with inactive individuals. This review supports a J-shaped relationship between physical activity level and energy intake. Further studies are required to confirm these findings. PROSPERO REGISTRATION NUMBER: CRD42015019696

Priming food intake with weight control cues: systematic review with a meta-analysis

Background A growing number of studies suggest that exposure to cues which are associated with weight control can prime or prompt controlled food intake in tempting food environments. However, findings are mixed and understanding which types of cues and for whom such cues may be most effective is needed to inform subsequent research and societal applications. A systematic review and meta-analysis were conducted to evaluate the effects of exposure to weight control cues compared with control cues on food intake. Methods PsycINFO, Medline, Embase and Web of Science were searched using key terms. Hedge’s g was used to calculate effect sizes based on mean food intake, standard deviations and sample sizes extracted from relevant publications and, a random effects model was used for the meta-analysis. Results Twenty-five articles consisting of 26 studies were eligible. Data from 25 studies (31 effect sizes) were available for the meta-analysis. Overall, weight control cues reduced food intake, albeit to a trivial effect (ES: -0.149, 95% CI: -0.271 to − 0.027). Subgroup analyses when studies which induced negative affect were removed showed that for individuals with strong weight control goals the effect was small-to-moderate (ES: -0.440, 95% CI: -0.718 to − 0.163), whereas for individuals with weak weight control goals this effect was trivial and non-significant (ES: 0.014, 95% CI: -0.249 to 0.278). Cue type and level of engagement did not significantly moderate the effect; however, specific cues (low-calorie foods and thin models) and attended engagement yielded significant effects. Caution is needed interpreting these findings as most studies were rated with high risk of bias and a number of studies could not be included in the subgroup analyses. Conclusions Based on the data available, weight control cues reduce food intake in individuals with strong weight control goals. Further research is needed to explore longer term effects of cue exposure and confirm underlying mechanisms. PROSPERO registry#CRD42016052396