24-h passive heat and cold exposures did not modify energy intake and appetite but strongly modify food reward.

Effects of acute thermal exposures on appetite appear hypothetical in reason of very heterogeneous methodologies. The aim of this study was therefore to clearly define the effects of passive 24-h cold (16°C) and heat (32°C) exposures on appetitive responses compared to a thermo neutral condition (24°C). Twenty-three healthy, young, and active male participants realised three sessions (from 1 pm) in a laboratory conceived like an apartment dressed with the same outfit (Clo=1). Three meals composed of three or four cold or warm dishes were served ad libitum to assess energy intake (EI). Leeds Food Preference Questionnaires were used before each meal to assess food reward. Subjective appetite was regularly assessed and levels of appetitive hormones (acylated ghrelin, GLP-1, leptin, and PYY) were assessed before and after the last meal (lunch). Contrary to the literature, total EI was not modified by cold or heat exposure (p=0.120). Accordingly, hunger scores (p=0.554) were not altered. Levels of acylated ghrelin and leptin were marginally higher during the 16 (p=0.032) and 32°C (p<0.023) sessions, respectively. Interestingly, implicit wanting for cold and low-fat foods at 32°C and for warm and high-fat foods at 16°C were increased during the whole exposure (p < 0.024). Moreover, cold entrées were more consumed at 32 °C (p<0.062) and warm main dishes more consumed at 16°C (p<0.025). Thus, passive cold and hot exposures had limited effects on appetite and it seems that offering some choice based on food temperature may help individuals to express their specific food preferences and maintain EI.

Increases in physical activity are associated with a faster rate of weight loss during dietary energy restriction in women with overweight and obesity.

This secondary analysis examined the influence of changes in physical activity (PA), sedentary time and energy expenditure (EE) during dietary energy restriction on the rate of weight loss (WL) and 1-year follow-up weight change in women with overweight/obesity.Measurements of body weight and composition (air-displacement plethysmography), resting metabolic rate (indirect calorimetry), total daily (TDEE) and activity EE (AEE), minutes of PA and sedentary time (PA monitor) were taken at baseline, after 2 weeks, after ≥5% WL or 12 weeks of continuous (25% daily energy deficit) or intermittent (75% daily energy deficit alternated with ad libitum day) energy restriction, and at 1-year post-WL. The rate of WL was calculated as total %WL/number of dieting weeks. Data from both groups were combined for analyses.Thirty-seven participants (age=35±10y; BMI=29.1±2.3kg/m2) completed the intervention (WL=-5.9±1.6%) and 18 returned at 1-year post-WL (weight change=+4.5±5.2%). Changes in sedentary time at 2 weeks were associated with the rate of WL during energy restriction (r=-0.38; p=0.03). Changes in total (r=0.54; p<0.01), light (r=0.43; p=0.01) and moderate-to-vigorous PA (r=0.55; p<0.01), sedentary time (r=-0.52; p<0.01), steps per day (r=0.39; p=0.02), TDEE (r=0.46; p<0.01) and AEE (r=0.51; p<0.01) during energy restriction were associated with the rate of WL. Changes in total (r=-0.50; p=0.04) and moderate-to-vigorous PA (r=-0.61; p=0.01) between post-WL and follow-up were associated with 1-year weight change (r=-0.51; p=0.04).These findings highlight that PA and sedentary time could act as modifiable behavioural targets to promote better weight outcomes during dietary energy restriction and/or weight maintenance.

The impact of 16-h heat exposure on appetite and food reward in adults.

Heat exposure is thought to reduce energy intake (EI) but studies are sparse and results not always concordant. The aim of this study was to examine whether a 16-h exposure to 32 °C leads to reduced EI compared to a control session (22 °C) and whether modifications in appetite sensations or food reward are implied. Sixteen healthy, lean, and active participants (9 women and 7 men, 25 ± 5 yo, body mass index: 22.0 ± 2.4 kg m-2) were passively exposed to two different thermal temperatures from 4:00 p.m. to 8:00 a.m. under controlled conditions. Hunger and thirst scores were regularly assessed using visual analogue scales. A fixed dinner meal (3670 ± 255 kJ) was consumed at 7:30 p.m. and an ad libitum breakfast buffet (20 foods/drinks varying in temperature, fat, and carbohydrate content) at 7:30 a.m. Components of reward (explicit liking [EL] and implicit wanting [EI]) for fat and sweet properties of food were assessed before each meal using the Leeds Food Preference Questionnaire (LFPQ). Ad libitum EI at breakfast did not differ between sessions (2319 ± 1108 vs 2329 ± 1141 kJ, in 22 and 32 °C sessions, respectively; p = 0.955). While thirst scores were higher in the 32 than the 22 °C session (p < 0.001), hunger scores did not differ (p = 0.580). EL and IW for high fat foods relative to low fat foods were decreased in 32 compared to 22 °C before dinner and breakfast (p < 0.001 for all). Although EI and hunger were not affected by a 16-h exposure to heat, modifications in food reward suggested a reduction in the preference of high-fat foods. Future research should investigate whether reduced EI in response to heat exposure is due to spontaneous selection of low-fat foods rather than altered appetite sensations.

Matched Weight Loss Through Intermittent or Continuous Energy Restriction Does Not Lead To Compensatory Increases in Appetite and Eating Behavior in a Randomized Controlled Trial in Women with Overweight and Obesity.

BACKGROUND: Continuous energy restriction (CER) is purported to be problematic because of reductions in fat-free mass (FFM), compensatory motivation to overeat, and weakened satiety. Intermittent energy restriction (IER) is an alternative behavioral weight loss (WL) strategy that may mitigate some of these limitations. OBJECTIVE: The objective of the DIVA study was to compare the effects of CER and IER on appetite when the degree of WL (≥5%) is matched. METHODS: Women with overweight/obesity (BMI 25.0-34.9 kg/m2; age 18-55 y) were recruited for this controlled-feeding RCT via CER (25% daily energy restriction) or IER (alternating ad libitum and 75% energy restriction days). Probe days were conducted at baseline and post-intervention to assess body composition, ad libitum energy intake and subjective appetite in response to a fixed-energy breakfast, and eating behavior traits. After baseline measurements, participants were allocated to CER (n = 22) or IER (n = 24). Per protocol analyses (≥5% WL within 12 wk) were conducted with use of repeated measures ANOVA. RESULTS: Thirty of 37 completers reached ≥5% WL [CER (n = 18): 6.3 ± 0.8% in 57 ± 16 d, IER (n = 12): 6.6 ± 1.1% in 67 ± 13 d; % WL P = 0.43 and days P = 0.10]. Fat mass [-3.9 (95% CI: -4.3, -3.4) kg] and FFM [-1.3 (95% CI: -1.6, -1.0) kg] were reduced post-WL (P < 0.001), with no group differences. Self-selected meal size decreased post-WL in CER (P = 0.03) but not in IER (P = 0.19). Hunger AUC decreased post-WL (P < 0.05), with no group differences. Satiety quotient remained unchanged and was similar in both groups. Both interventions improved dietary restraint, craving control, susceptibility to hunger, and binge eating (P < 0.001). CONCLUSIONS: Controlled ≥5% WL via CER or IER did not differentially affect changes in body composition, reductions in hunger, and improvements in eating behavior traits. This suggests that neither CER nor IER lead to compensatory adaptations in appetite in women with overweight/obesity. This trial was registered at clinicaltrials.gov as NCT03447600.

Patients with Long COVID continue to experience significant symptoms at 12 months and factors associated with improvement: A prospective cohort study in France (PERSICOR).

OBJECTIVES: This study examines long COVID symptoms course over 12 months, their impact on daily life, and associated factors for symptom relief. METHODS: A prospective cohort study included 231 participants with long COVID at 12-month follow-up. Data on characteristics, symptom course, and remission were collected using a questionnaire and a remission scale. Poisson regression models were used to estimate the prevalence rate ratio (PRR) and 95% confidence intervals (CIs) for factors associated with symptom improvement. RESULTS: Of the 231 participants, 63.2% developed SARS-CoV-2 antibodies before COVID-19 vaccination. At 12 months, only 8.7% (95% CI: 5.4-13.1%) reported complete remission, while 28.6% noted significant improvement. Most symptoms remained prevalent: asthenia (83.1%), neurocognitive/neurological (93.9%), cardiothoracic (77.9%), Musculoskeletal (78.8%). During long COVID, 62.2% stopped working, and only 32.5% resumed full-time professional activities. Presence of SARS-CoV-2 antibodies before vaccination increased the probability of improvement (aPRR: 1.60, P = 0.028), while ageusia at initial long COVID phase decreased the probability (aPRR: 0.38, P = 0.007). CONCLUSIONS: Long-COVID symptoms persisted in the majority of participants after 12 months, with significant impacts on daily life and work. SARS-CoV-2 antibodies were associated with better prognosis, while persistent ageusia indicated a lower probability of improvement. These findings highlight the need for ongoing support and care for individuals with long COVID.

Co-Design of a Voice-Based Digital Health Solution to Monitor Persisting Symptoms Related to COVID-19 (UpcomingVoice Study): Protocol for a Mixed Methods Study.

BACKGROUND: Between 10% and 20% of people with a COVID-19 infection will develop the so-called long COVID syndrome, which is characterized by fluctuating symptoms. Long COVID has a high impact on the quality of life of affected people, who often feel abandoned by the health care system and are demanding new tools to help them manage their symptoms. New digital monitoring solutions could allow them to visualize the evolution of their symptoms and could be tools to communicate with health care professionals (HCPs). The use of voice and vocal biomarkers could facilitate the accurate and objective monitoring of persisting and fluctuating symptoms. However, to assess the needs and ensure acceptance of this innovative approach by its potential users-people with persisting COVID-19-related symptoms, with or without a long COVID diagnosis, and HCPs involved in long COVID care-it is crucial to include them in the entire development process. OBJECTIVE: In the UpcomingVoice study, we aimed to define the most relevant aspects of daily life that people with long COVID would like to be improved, assess how the use of voice and vocal biomarkers could be a potential solution to help them, and determine the general specifications and specific items of a digital health solution to monitor long COVID symptoms using vocal biomarkers with its end users. METHODS: UpcomingVoice is a cross-sectional mixed methods study and consists of a quantitative web-based survey followed by a qualitative phase based on semistructured individual interviews and focus groups. People with long COVID and HCPs in charge of patients with long COVID will be invited to participate in this fully web-based study. The quantitative data collected from the survey will be analyzed using descriptive statistics. Qualitative data from the individual interviews and the focus groups will be transcribed and analyzed using a thematic analysis approach. RESULTS: The study was approved by the National Research Ethics Committee of Luxembourg (number 202208/04) in August 2022 and started in October 2022 with the launch of the web-based survey. Data collection will be completed in September 2023, and the results will be published in 2024. CONCLUSIONS: This mixed methods study will identify the needs of people affected by long COVID in their daily lives and describe the main symptoms or problems that would need to be monitored and improved. We will determine how using voice and vocal biomarkers could meet these needs and codevelop a tailored voice-based digital health solution with its future end users. This project will contribute to improving the quality of life and care of people with long COVID. The potential transferability to other diseases will be explored, which will contribute to the deployment of vocal biomarkers in general. TRIAL REGISTRATION: ClinicalTrials.gov NCT05546918; https://clinicaltrials.gov/ct2/show/NCT05546918. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/46103.

Food Reward after Bariatric Surgery and Weight Loss Outcomes: An Exploratory Study.

Changes in food preferences after bariatric surgery may alter its effectiveness as a treatment for obesity. We aimed to compare food reward for a comprehensive variety of food categories between patients who received a sleeve gastrectomy (SG) or a Roux-en-Y gastric bypass (RYGB) and to explore whether food reward differs according to weight loss. In this cross-sectional exploratory study, food reward was assessed using the Leeds Food Preference Questionnaire (LFPQ) in patients at 6, 12, or 24 months after SG or RYGB. We assessed the liking and wanting of 11 food categories. Comparisons were done regarding the type of surgery and total weight loss (TWL; based on tertile distribution). Fifty-six patients (30 SG and 26 RYGB) were included (women: 70%; age: 44.0 (11.1) y). Regarding the type of surgery, scores were not significantly different between SG and RYGB, except for 'non-dairy products-without color' explicit liking (p = 0.04). Regarding TWL outcomes, explicit liking, explicit wanting, and implicit wanting, scores were significantly higher for good responders than low responders for 'No meat-High fat' (post-hoc corrected p-value: 0.04, 0.03, and 0.04, respectively). Together, our results failed to identify major differences in liking and wanting between the types of surgery and tended to indicate that higher weight loss might be related to a higher reward for high protein-content food. Rather focus only on palatable foods, future studies should also consider a broader range of food items, including protein reward.

Long COVID Classification: Findings from a Clustering Analysis in the Predi-COVID Cohort Study.

The increasing number of people living with Long COVID requires the development of more personalized care; currently, limited treatment options and rehabilitation programs adapted to the variety of Long COVID presentations are available. Our objective was to design an easy-to-use Long COVID classification to help stratify people with Long COVID. Individual characteristics and a detailed set of 62 self-reported persisting symptoms together with quality of life indexes 12 months after initial COVID-19 infection were collected in a cohort of SARS-CoV-2 infected people in Luxembourg. A hierarchical ascendant classification (HAC) was used to identify clusters of people. We identified three patterns of Long COVID symptoms with a gradient in disease severity. Cluster-Mild encompassed almost 50% of the study population and was composed of participants with less severe initial infection, fewer comorbidities, and fewer persisting symptoms (mean = 2.9). Cluster-Moderate was characterized by a mean of 11 persisting symptoms and poor sleep and respiratory quality of life. Compared to the other clusters, Cluster-Severe was characterized by a higher proportion of women and smokers with a higher number of Long COVID symptoms, in particular vascular, urinary, and skin symptoms. Our study evidenced that Long COVID can be stratified into three subcategories in terms of severity. If replicated in other populations, this simple classification will help clinicians improve the care of people with Long COVID.

Long COVID Symptomatology After 12 Months and Its Impact on Quality of Life According to Initial Coronavirus Disease 2019 Disease Severity.

Background: "Long COVID" is characterized by a variety of symptoms and an important burden for affected people. Our objective was to describe long COVID symptomatology according to initial coronavirus disease 2019 (COVID-19) severity. Methods: Predi-COVID cohort study participants, recruited at the time of acute COVID-19 infection, completed a detailed 12-month symptom and quality of life questionnaire. Frequencies and co-occurrences of symptoms were assessed. Results: Among the 289 participants who fully completed the 12-month questionnaire, 59.5% reported at least 1 symptom, with a median of 6 symptoms. Participants with an initial moderate or severe acute illness declared more frequently 1 or more symptoms (82.6% vs 38.6%, P < .001) and had on average 6.8 more symptoms (95% confidence interval, 4.18-9.38) than initially asymptomatic participants who developed symptoms after the acute infection. Overall, 12.5% of the participants could not envisage coping with their symptoms in the long term. Frequently reported symptoms, such as neurological and cardiovascular symptoms, but also less frequent ones such as gastrointestinal symptoms, tended to cluster. Conclusions: Frequencies and burden of symptoms present 12 months after acute COVID-19 infection increased with the severity of the acute illness. Long COVID likely consists of multiple subcategories rather than a single entity. This work will contribute to the better understanding of long COVID and to the definition of precision health strategies. Clinical Trials Registration: NCT04380987.

An exploratory investigation of the impact of 'fast' and 'feed' days during intermittent energy restriction on free-living energy balance behaviours and subjective states in women with overweight/obesity.

BACKGROUND/OBJECTIVES: This controlled-feeding randomised controlled trial examined free-living appetite and physical activity (PA) on 'fast' and 'feed' days during intermittent energy restriction (IER), compared to continuous energy restriction (CER). SUBJECTS/METHODS: Forty-six women with overweight/obesity (age = 35 ± 10 years, BMI = 29.1 ± 2.3 kg/m2) were randomised to IER (n = 24; alternate fast days at 25% energy requirements and ad libitum feed days) or CER (n = 22; 75% energy requirements daily) to ≥5% weight loss (WL) or up to 12 weeks. Self-reported energy intake (EI; online food record), objectively measured PA (SenseWear Armband) and retrospective daily hunger and food cravings were measured over 7 days at baseline, week 2 and final week. Intent-to-treat analyses were performed using linear mixed models. RESULTS: Final WL (MΔ = 4.7 [95% confidence interval 4.2, 5.2] kg, 5.9%) did not differ between IER and CER (interaction P = 0.307). During IER, feed-day EI did not differ from baseline and was lower in the final week compared to week 2 (MΔ = 295 [81, 509] kcal, P = 0.004). Daily hunger was greater on fast compared to feed days (MΔ = 15 [10, 21] mm, P < 0.001), but food cravings did not differ. Light PA was lower on fast relative to feed days (MΔ = 18 [2, 34] min/day, P = 0.024), with no other differences in PA. Compared to CER, IER increased hunger and led to smaller improvements in craving control (both interactions P ≤ 0.034). CONCLUSIONS: IER fast days were associated with increased free-living hunger and lower light PA compared to feed days, but had no impact on food cravings or self-reported ad libitum daily EI. IER may be less favourable than CER for the free-living day-to-day control of hunger and food cravings.

[Patient experience, epistemic authority and health challenges: the example of long COVID]. / Expérience patient, autorité épistémique et enjeux sanitaires : l'exemple du Covid long.

Since February 2020, hundreds of thousands of patients have been left with persistant symptoms after their infection. Along with their clinicians, these patients are exposed to a high degree of uncertainty and the urgent need to produce conceptual frameworks aimed at recognising, treating and validating their experience as patients suffering from new and protracted symptoms and witnessing debates as to how these symptoms should be qualified. In this respect, long covid illustrates the need to combine the collective experiential knowledge of patients and scientific knowledge for the benefit of the patients, clinicians and research.

Food Liking but Not Wanting Decreases after Controlled Intermittent or Continuous Energy Restriction to ≥5% Weight Loss in Women with Overweight/Obesity.

Food reward (i.e., liking and wanting) has been shown to decrease after different types of weight management interventions. However, it is unknown whether specific dietary modalities (continuous (CER) vs. intermittent (IER) energy restriction) have differing effects on liking and implicit wanting after weight loss (WL) and whether these changes are sustained after 1-year of no-contact. Women with overweight or obesity (age 18-55 years) were randomly allocated to controlled-feeding CER (25% daily energy restriction) or IER (alternating ad libitum and 75% energy restriction days). Study visits were conducted at baseline, post-WL (to ≥5% WL within 12 weeks) and 1-year post-WL. The main outcomes were liking and implicit wanting for 4 categories of common food varying in fat and taste assessed by the Leeds Food Preference Questionnaire. Linear mixed models were conducted on the 30 participants achieving ≥5% WL and 15 returners. After an initial WL of -5.1 ± 0.2 kg, after 1-year 2.6 ± 0.5 kg were regained. Liking but not wanting decreased after WL. Food reward after 1-year did not differ from baseline, but the high loss to follow-up prevents generalization. IER and CER did not differ in their effects on food reward during WL or at 1-year follow-up.

An augmented food strategy leads to complete energy compensation during a 15-day military training expedition in the cold.

Soldiers on military expeditions usually fail to compensate for the increase in energy expenditure, with potential deleterious consequences. We therefore analyzed the characteristics of energy compensation in 12 male soldiers, during a 15-day expedition in the cold, while alleviating some of the contextual limitations of food intake (~20-MJ daily bags of easy-to-use, highly palatable and familiar foods with multiple and long breaks allowed during the day). Body and fat mass losses were low and moderate, respectively (-1.13 ± 1.42% and -19.5 ± 15.6%, respectively, p < .021). Mean energy intake (EI) was high (~16.3 MJ) and increased at each third of the expedition (15.3 ± 2.1, 16.1 ± 2.1, and 17.6 ± 2.0 for D1-5, D6-10 and D11-15, respectively, p < .012). This resulted in reaching a neutral energy balance as soon as the D6 to 10 period and reaching normal energy availability during D11 to 15. Participants only increased their EI during the mid-day (10:00-14:00) period (p = .002) whereas hunger and thirst only increased in the morning, with higher scores during D11-15 than D1-5 (p < .009). Last, the reward value of sweet foods was also higher during D11-15 than during D1-5 (p = .026). The changes in body mass were positively associated with EI (r = 0.598, p = .040) and carbohydrate intake (r = 0.622, p = .031). This study indicates that complete energy compensation can be reached in challenging field conditions when food intake is facilitated, offering some guidelines to limit energy deficit during operational missions.

Body Fatness Influences Associations of Body Composition and Energy Expenditure with Energy Intake in Healthy Women.

OBJECTIVE: This study aimed to investigate the influence of body fatness on the associations of body composition and energy expenditure (EE) with energy intake (EI). METHODS: Data from 93 women (BMI = 25.5 [SD 4.2] kg/m2 ) recruited for two studies (Study 1, n = 48, BMI = 25.0-34.9 kg/m2 ; Study 2, n = 45, BMI = 18.5-24.9 kg/m2 ) were examined. Body composition, resting metabolic rate (RMR), and test meal EI were assessed during a laboratory probe day. Physical activity, total daily EE (TDEE), and self-reported free-living 24-hour EI were collected during 7 days. RESULTS: In the whole sample, fat-free mass (r = 0.45; P < 0.001), RMR (r = 0.41; P < 0.001), and TDEE (r = 0.39; P < 0.001), but not fat mass (r = 0.17; P = 0.11), were positively associated with free-living 24-hour EI. Body fat percentage moderated the associations of RMR (ß = -1.88; P = 0.02) and TDEE (ß = -1.91; P = 0.03) with mean free-living 24-hour EI. Fat mass was negatively associated with test meal EI only in the leaner group (r = -0.43; P = 0.004), and a weak nonlinear association was observed in the whole sample (r2 = 0.092; P = 0.04). CONCLUSIONS: Body fat percentage appears to moderate the associations between EE and daily EI. Furthermore, the negative association between fat mass and test meal EI observed in leaner individuals was absent in those with higher body fatness. Therefore, higher levels of body fatness may weaken the coupling between EE and EI.

The Impact of Physical Activity on Food Reward: Review and Conceptual Synthesis of Evidence from Observational, Acute, and Chronic Exercise Training Studies.

PURPOSE OF REVIEW: This review brings together current evidence from observational, acute, and chronic exercise training studies to inform public debate on the impact of physical activity and exercise on food reward. RECENT FINDINGS: Low levels of physical activity are associated with higher liking and wanting for high-energy food. Acute bouts of exercise tend to reduce behavioral indices of reward for high-energy food in inactive individuals. A dissociation in liking (increase) and wanting (decrease) may occur during chronic exercise training associated with loss of body fat. Habitual moderate-to-vigorous physical activity is associated with lower liking and wanting for high-fat food, and higher liking for low-fat food. Food reward does not counteract the benefit of increasing physical activity levels for obesity management. Exercise training appears to be accompanied by positive changes in food preferences in line with an overall improvement in appetite control.

Exercise Training Reduces Reward for High-Fat Food in Adults with Overweight/Obesity.

PURPOSE: There is increasing evidence that exercise training may facilitate weight management via improvements in homeostatic appetite control, but little is known about how exercise training affects food reward and susceptibility to overeating. METHODS: This study examined changes in food reward and eating behavior traits after a supervised 12-wk exercise intervention (10.5 MJ·wk) in inactive individuals with overweight/obesity (exercisers; n = 46, 16 men/30 women; mean (SD) body mass index, 30.6 (3.8) kg·m; and mean (SD) age, 43.2 (7.5) yr) compared with nonexercising controls (n = 15; 6 men/9 women; mean (SD) body mass index, 31.4 (3.7) kg·m; and mean (SD) age, 41.4 (10.7) yr). Liking and wanting scores for high-fat relative to low-fat foods were assessed with the Leeds Food Preference Questionnaire before and after consumption of an isoenergetic high-fat or high-carbohydrate lunch. Eating behavior traits were assessed using the Three-Factor Eating Questionnaire and Binge Eating Scale. RESULTS: A week-group interaction indicated that wanting scores decreased from baseline to postintervention in exercisers only (M[INCREMENT]Pre-Post = -4.1, P = 0.03, ηp = 0.09, 95% confidence interval [CI], -7.8 to -0.4), but there was no exercise effect on liking. There was also a week-group interaction for binge eating, which decreased in exercisers only (M[INCREMENT]Pre-Post = -1.5, P = 0.01, ηp = 0.11; 95% CI, -2.7 to -0.4). A small reduction in disinhibition was also apparent in exercisers (M[INCREMENT]Pre-Post = -0.7, P = 0.02, ηp = 0.10; 95% CI, -1.3 to -0.1). CONCLUSIONS: This study showed that 12 wk of exercise training reduced wanting scores for high-fat foods and trait markers of overeating in individuals with overweight/obesity compared with nonexercising controls. Further research is needed to elucidate the mechanisms behind these exercise-induced changes in food reward.

Impact of Meal Timing and Chronotype on Food Reward and Appetite Control in Young Adults.

Early meal timing and chronotype are associated with lower BMI, but their impact on appetite is poorly understood. We examined the impact of meal timing and chronotype on appetite and food reward. Forty-four adults were divided into early (EC; Morningness-Eveningness Questionnaire (MEQ) score = 55 ± 5) or late chronotype (LC; MEQ score = 40 ± 6) and assessed for body mass index, habitual energy intake (EI; three-day online dietary record) and eating behavior traits from the Three-Factor Eating Questionnaire (TFEQ). Participants attended the laboratory after ≥3 h fast on two occasions for early (AM; 8-10 a.m.) and late (PM; 4-6 p.m.) counterbalanced testing sessions in a 2 × 2 design. Appetite ratings and food reward (validated diurnal Leeds Food Preference Questionnaire) were measured in response to a standardized test meal. LC was associated with higher BMI (p = 0.01), but not with EI or TFEQ. The composite appetite score was lower in AM than PM (MΔ= -5 (95% CI -10, -0.2) mm, p = 0.040). Perceived test meal fillingness was higher in AM than PM and EC compared to LC (p ≤ 0.038). Liking and wanting high-fat food were lower in AM than PM (p ≤ 0.004). The late chronotype was associated with greater desire for high-fat food (p = 0.006). To conclude, early meal timing and early chronotype are independently associated with smaller appetite and lower desire for high-fat food.

Eating Behavior, Physical Activity and Exercise Training: A Randomized Controlled Trial in Young Healthy Adults.

Regular physical activity (PA) is an important part of the treatment of several medical conditions, including overweight and obesity, in which there may be a weakened appetite control. Eating behaviour traits influence weight control and may be different in active and sedentary subjects. This paper reports the relationships between the time spent in sedentary behaviour and physical activity (PA) of different intensity, and eating behaviour traits in young, healthy adults. Additionally, it reports the results of a six-month-long, randomized, controlled trial to examine the effect of an exercise intervention on eating behaviour traits. A total of 139 young (22.06 ± 2.26 years) healthy adults (68.35% women) with a Body Mass Index (BMI) of 24.95 ± 4.57 kg/m2 were enrolled. Baseline assessments of habitual PA were made using wrist-worn triaxial accelerometers; eating behaviour traits were examined via the self-reported questionnaires: Binge Eating, Three-Factor Eating Questionnaire-R18 and Control of Eating Questionnaire. The subjects were then randomly assigned to one of three groups: control (usual lifestyle), moderate-intensity exercise (aerobic and resistance training 3¨C4 days/week at a heart rate equivalent to 60% of the heart rate reserve (HRres) for the aerobic component, and at 50% of the 1 repetition maximum (RM) for the resistance component), or vigorous-intensity exercise (the same training but at 80% HRres for half of the aerobic training, and 70% RM for the resistance training). At baseline, sedentary behaviour was inversely associated with binge eating (r = -0.181, p < 0.05) and with uncontrolled eating (r = -0.286, p = 0.001). Moderate PA (MPA) was inversely associated with craving control (r = -0.188, p < 0.05). Moderate-to-vigorous PA (MVPA) was directly associated with binge eating (r = 0.302, p < 0.001) and uncontrolled eating (r = 0.346, p < 0.001), and inversely associated with craving control (r = -0.170, p < 0.015). Overall, PA was directly associated with binge eating (r = 0.275, p = 0.001), uncontrolled eating (r = 0.321, p < 0.001) and emotional eating (r = 0.204, p < 0.05). Additionally, only emotional eating was modified by the intervention, increasing in the vigorous-intensity exercise group (p < 0.05). In summary, we observed that time spent in sedentary behaviour/PA of different intensity is associated with eating behaviour traits, especially binge eating in young adults. In contrast, the six-month exercise intervention did not lead to appreciable changes in eating behaviour traits.

Issues in Measuring and Interpreting Human Appetite (Satiety/Satiation) and Its Contribution to Obesity.

PURPOSE OF REVIEW: The goals of this paper are to report current research practices in investigations of human appetite control and to assess their relationships with emerging theoretical principles. Appetite is often distinguished by the separation of homeostatic and hedonic processes. RECENT FINDINGS: This report assesses the validity of a homeostatic toolkit to measure subjectively perceived hunger and its relationship to the developing processes of satiation (control of meal size) and satiety (control of the post-eating period). The capacity of a procedure to measure the influence of hedonic processes on food intake is also evaluated. A major issue is the relationship between the pattern of eating behaviour (influenced by the underlying drive to eat and the inhibition induced by the act of eating itself) and the parallel underlying profile of hormonal and other metabolic biomarkers. Increasing recognition is being given to individual variability in the expression of appetite, and the fact that the use of the average (mean) response conceals important information about the nature of appetite control. There is a growing interest in the identification of satiety phenotypes that operate in parallel to metabolic phenotypes. Interestingly, energy expenditure (metabolic and behavioural) contributes to an energy balance framework for understanding energy intake (appetite).