The impact of time-restricted eating on health-related quality of life: a systematic literature review.

CONTEXT: Time-restricted eating (TRE) is a novel dietary intervention shown to facilitate weight loss and improve metabolic health. However, like any dietary intervention, long-term success largely depends on individual adherence, which can be influenced by whether the intervention impacts the individual's health-related quality of life (HR-QoL). Despite the growing body of research investigating TRE as a dietary approach and its potential impact on HR-QoL in adults, to date there has been no systematic review to summarize these findings. OBJECTIVE: To examine the impact of TRE on HR-QoL in adults. DATA SOURCES: All randomized controlled trials, pre-post and pilot/feasibility studies were searched in PubMed, EMBASE via Ovid, CINAHL, Cochrane Library, and PsycINFO via Ovid until March 20, 2023. DATA EXTRACTION: Two researchers were involved in the screening and paper selection process. A single researcher extracted all relevant data from eligible studies. CONCLUSION: Overall, 10 studies were eligible for inclusion in this systematic review. Four studies reported improvements in overall HR-QoL scores among participants with type 2 diabetes, middle-aged women with obesity, generally healthy adults, and generally healthy adult employees. Three studies reported significant and nonsignificant improvements in some domains of HR-QoL assessment tools among overweight, sedentary older adults, overweight or obese adults, and 24-hour shift workers. No studies reported that TRE adversely affected HR-QoL. Improvements in HR-QoL appeared to occur primarily at 12 weeks/3 months. There was no clear relationship between HR-QoL scores and TRE protocol, additional study outcomes, participant health status, age, or adherence. Although further research is required to elucidate the impact of TRE on HR-QoL, the findings reveal that no studies show that TRE adversely affects HR-QoL. SYSTEMATIC REVIEW REGISTRATION: Open Science Framework (OSF) (The Impact of Time-Restricted Eating on Health-Related Quality of Life: A Systematic Review; https://doi.org/10.17605/OSF.IO/9NK45).

Exploring Australian Dietitians' knowledge, experience and perspectives of time-restricted eating in private practice: A qualitative study.

Time-restricted eating is a novel nutrition intervention with evidence of beneficial effects on weight loss, blood glucose management, and other metabolic health outcomes. Adherence to time-restricted eating is higher than some traditional nutrition interventions to support individuals living with overweight/obesity and type 2 diabetes mellitus. However, there may be an evidence-practice gap of time-restricted eating in Australian dietetic practice. The present study aimed to explore dietitians' knowledge, experiences, and perspectives of time-restricted eating and timing of eating advice in practice. Semi-structured interviews with 10 private practice dietitians across Australia were conducted. Audio recordings were transcribed and analysed thematically. Six themes were identified: (i) distinction of time-restricted eating to other fasting protocols; (ii) knowledge of health benefits of time-restricted eating; (iii) patient-led advice frequently given: timing of breakfast and dinner; (iv) dietitian-led advice frequently given: eating cut-off time to avoid late night snacking; (v) barriers and facilitators to offering time-restricted eating or timing of eating advice; (vi) timing of eating advice within professional guidelines and resources. These findings suggest the need for development of professional resources and educational development tools for dietitians on time-restricted eating.

Effectiveness of an anti-inflammatory diet versus low-fat diet for knee osteoarthritis: the FEAST randomised controlled trial protocol.

INTRODUCTION: Chronic inflammation plays a key role in knee osteoarthritis pathophysiology and increases risk of comorbidities, yet most interventions do not typically target inflammation. Our study will investigate if an anti-inflammatory dietary programme is superior to a standard care low-fat dietary programme for improving knee pain, function and quality-of-life in people with knee osteoarthritis. METHODS AND ANALYSIS: The eFEct of an Anti-inflammatory diet for knee oSTeoarthritis study is a parallel-group, assessor-blinded, superiority randomised controlled trial. Following baseline assessment, 144 participants aged 45-85 years with symptomatic knee osteoarthritis will be randomly allocated to one of two treatment groups (1:1 ratio). Participants randomised to the anti-inflammatory dietary programme will receive six dietary consultations over 12 weeks (two in-person and four phone/videoconference) and additional educational and behaviour change resources. The consultations and resources emphasise nutrient-dense minimally processed anti-inflammatory foods and discourage proinflammatory processed foods. Participants randomised to the standard care low-fat dietary programme will receive three dietary consultations over 12 weeks (two in-person and one phone/videoconference) consisting of healthy eating advice and education based on the Australian Dietary Guidelines, reflecting usual care in Australia. Adherence will be assessed with 3-day food diaries. Outcomes are assessed at 12 weeks and 6 months. The primary outcome will be change from baseline to 12 weeks in the mean score on four Knee injury and Osteoarthritis Outcome Score (KOOS4) subscales: knee pain, symptoms, function in daily activities and knee-related quality of life. Secondary outcomes include change in individual KOOS subscale scores, patient-perceived improvement, health-related quality of life, body mass and composition using dual-energy X-ray absorptiometry, inflammatory (high-sensitivity C reactive protein, interleukins, tumour necrosis factor-α) and metabolic blood biomarkers (glucose, glycated haemoglobin (HbA1c), insulin, liver function, lipids), lower-limb function and physical activity. ETHICS AND DISSEMINATION: The study has received ethics approval from La Trobe University Human Ethics Committee. Results will be presented in peer-reviewed journals and at international conferences. TRIAL REGISTRATION NUMBER: ACTRN12622000440729.

Effect of high-fat diet and morning or evening exercise on lipoprotein subfraction profiles: secondary analysis of a randomised trial.

We investigated the effect of a high-fat diet (HFD) on serum lipid subfractions in men with overweight/obesity and determined whether morning or evening exercise affected these lipid profiles. In a three-armed randomised trial, 24 men consumed an HFD for 11 days. One group of participants did not exercise (n = 8, CONTROL), one group trained at 06:30 h (n = 8, EXam), and one group at 18:30 h (n = 8, EXpm) on days 6-10. We assessed the effects of HFD and exercise training on circulating lipoprotein subclass profiles using NMR spectroscopy. Five days of HFD induced substantial perturbations in fasting lipid subfraction profiles, with changes in 31/100 subfraction variables (adjusted p values [q] < 0.05). Exercise training induced a systematic change in lipid subfraction profiles, with little overall difference between EXam and EXpm. Compared with CONTROL, exercise training reduced serum concentrations of > 20% of fasting lipid subfractions. EXpm reduced fasting cholesterol concentrations in three LDL subfractions by ⁓30%, while EXam only reduced concentration in the largest LDL particles by 19% (all q < 0.05). Lipid subfraction profiles changed markedly after 5 days HFD in men with overweight/obesity. Both morning and evening exercise training impacted subfraction profiles compared with no exercise.

Time-restricted eating improves measures of daily glycaemic control in people with type 2 diabetes.

AIMS: Examine the effect of 5 d/wk, 9-h time-restricted eating (TRE) protocol on 24-h glycaemic control in adults with type 2 diabetes (T2D). METHODS: Nineteen adults with T2D (10 F/9 M; 50 ± 9 y, HbA1c 7.6% (60 mmol/mol), BMI ∼34 kg/m2) completed a pre-post non-randomised trial comprising of a 2-wk Habitual monitoring period followed by 9-h (10:00-19:00 h) TRE for 4-wk. Glycaemic control was assessed via continuous glucose monitoring (CGM; for mean 24-h glucose concentrations, 24-h total area under the curve (AUC) and glucose variability metrics), with dietary records and physical activity monitoring. Changes in CGM measures, dietary intake and physical activity were assessed with linear mixed-effects models. RESULTS: TRE did not alter dietary energy intake, macronutrient composition or physical activity, but reduced the daily eating window (-2 h 35 min, P < 0.001). Compared to the Habitual period, 24-h glucose concentrations (mean, SD) and AUC decreased in the 4-wk TRE period (mean: -0.7 ± 1.2 mmol/L, P = 0.02; SD: -0.2 ± 0.3 mmol/L, P = 0.01; 24-h AUC: -0.9 ± 1.4 mmol/L⋅h-1 P = 0.01). During TRE, participants spent 10% more time in range (3.9-10.0 mmol/L; P = 0.02) and 10% less time above range (>10.0 mmol/L; P = 0.02). CONCLUSIONS: Adhering 5 d/wk. to 9-h TRE improved glycaemic control in adults with T2D, independent of changes in physical activity or dietary intake. CLINICAL TRIAL REGISTRATION: Australia New Zealand Clinical Trial Registry, ACTRN12618000938202.

Attitudes and Opinions of Parents towards Water-Only Drink Policy at Junior Triathlon Events.

Rates of childhood obesity within Australia continue to rise, with consumption of sugar-sweetened beverages one contributing factor. Community sport provides an opportunity to implement policies promoting water as the beverage of choice. However, the attitudes of parents toward a water-only policy are not known. This cross-sectional study aimed to investigate parents' opinions towards beverage consumption and a water-only policy. Data were collected from participants (n = 159) using an investigator-designed questionnaire, administered using iPads, at a junior Triathlon Victoria event. Water was the most popular beverage provided before (75%), during (85%) and after (61%) sport. Parents were more likely to provide sports drinks to children older than 14 years (27%). Three-quarters (77%) of parents reported having received no information regarding hydration requirements. Parents rated the importance of hydration prior to, during and after a triathlon as high (9.08 ± 1.2, 8.76 ± 1.3 and 9.30 ± 0.4 out of 10, respectively). Parents were supportive of a water-only policy at all junior triathlon events and all junior sporting events (7.94 ± 1.3 and 7.86 ± 1.9, respectively). There was less support for a water-only policy for adult triathlons (6.40 ± 3.1). A water-only drink policy at junior sport is viewed positively by parents. This warrants further research and policy development to facilitate behaviour change.

Perspective: Time-Restricted Eating-Integrating the What with the When.

Time-restricted eating (TRE) is a popular dietary strategy that emphasizes the timing of meals in alignment with diurnal circadian rhythms, permitting ad libitum energy intake during a restricted (∼8-10 h) eating window each day. Unlike energy-restricted diets or intermittent fasting interventions that focus on weight loss, many of the health-related benefits of TRE are independent of reductions in body weight. However, TRE research to date has largely ignored what food is consumed (i.e., macronutrient composition and energy density), overlooking a plethora of past epidemiological and interventional dietary research. To determine some of the potential mechanisms underpinning the benefits of TRE on metabolic health, future studies need to increase the rigor of dietary data collected, assessed, and reported to ensure a consistent and standardized approach in TRE research. This Perspective article provides an overview of studies investigating TRE interventions in humans and considers dietary intake (both what and when food is eaten) and their impact on selected health outcomes (i.e., weight loss, glycemic control). Integrating existing dietary knowledge about what food is eaten with our recent understanding on when food should be consumed is essential to optimize the impact of dietary strategies aimed at improving metabolic health outcomes.

An anti-inflammatory diet intervention for knee osteoarthritis: a feasibility study.

BACKGROUND: Knee osteoarthritis has an inflammatory component that is linked to pain and joint pathology, yet common non-surgical and non-pharmacological interventions (e.g., exercise, calorie restricting diets) do not typically target inflammation. We aimed to evaluate the feasibility of a telehealth delivered anti-inflammatory diet intervention for knee osteoarthritis. METHODS: This 9-week single-arm feasibility study recruited participants aged 40-85 years with symptomatic knee osteoarthritis (inclusion criteria: average pain ≥4/10 or maximal pain ≥5/10 during past week). All participants received a telehealth-delivered anti-inflammatory dietary education intervention involving 1:1 consultations at baseline, 3- and 6-week follow-up. The diet emphasised nutrient-dense wholefoods and minimally processed anti-inflammatory foods and discouraged processed foods considered to be pro-inflammatory. The primary outcome of feasibility was assessed via: i) eligibility, recruitment and retention rates; ii) self-reported dietary adherence; iii) adverse events; and iv) treatment satisfaction. Post-intervention interviews evaluated the acceptability of the dietary intervention delivered via telehealth. Secondary outcomes included changes in self-reported body mass, Knee injury and Osteoarthritis Outcome Score (KOOS), health-related quality of life (EuroQoL-5D), analgesic use and global rating of change. Worthwhile effects were determined by the minimal detectable change (MDC) for all five KOOS-subscales (pain, symptoms, activities of daily living, sport/recreation, quality of life) being contained within the 95% confidence interval. RESULTS: Forty-eight of seventy-three (66%) individuals screened were eligible and 28 enrolled over 2 months (82% female, mean age 66 ± 8 years, body mass index 30.7 ± 4.8 kg.m-2). Six participants withdrew prior to final follow-up (21% drop-out). Of those with final follow-up data, attendance at scheduled telehealth consultations was 99%. Self-reported adherence to diet during the 9-week intervention period: everyday = 27%, most of time = 68% and some of time = 5%. Two minor adverse events were reported. Change scores contained the MDC within the 95% confidence interval for all five KOOS subscales. Suggestions to improve study design and limit drop-out included an initial face-to-face consultation and more comprehensive habitual dietary intake data collection. CONCLUSION: This study supports the feasibility of a full-scale randomised controlled trial to determine the efficacy of a primarily telehealth-delivered anti-inflammatory dietary education intervention in adults with symptomatic knee osteoarthritis. TRIAL REGISTRATION: ACTRN12620000229976 prospectively on 25/2/2020.

A systematic review update of athletes' nutrition knowledge and association with dietary intake.

Athletes' dietary intakes sometimes do not meet sports nutrition guidelines. Nutrition knowledge (NK) is one factor that may influence dietary intake, but NK measurement tools are often outdated or unvalidated, and results regarding athletes' NK are equivocal. The aims of this systematic review were to update previous systematic reviews by examining athletes' NK and to assess the relationship between athletes' general NK, sport NK and dietary intake. MEDLINE, CINAHL, Scopus, SPORTDiscus, Web of Science and Cochrane were searched for studies published between November 2015 and November 2020 that provided a quantitative measure of NK and described the NK tool used. Twenty-eight studies were included, study quality was assessed using JBI checklists and data on NK score and diet intake was extracted. Eight studies utilised validated, up-to-date NK measurement tools. Mean general and sport NK% scores varied between 40·2% ± 12·4 and 70 % ± 9. Mean protein and carbohydrate consumption was 1·1-3·4 g/kg.bw/d and 2·4-4·6 g/kg.bw/d, respectively. Weak-to-moderate, positive associations were found between NK and positive dietary behaviours. Due to a wide variety of NK measurement tools used, it is difficult to synthesise results to determine overall NK in athletes. Overall, there appears to be a low standard of knowledge. Quality of measurement tools for NK has improved but remains an issue. Future studies should use relevant, current validated NK tools or validate tools in their study population. More research is needed into the relationship between NK and other modifiable factors influencing dietary intake.

The effect of morning vs evening exercise training on glycaemic control and serum metabolites in overweight/obese men: a randomised trial.

AIMS/HYPOTHESIS: We determined whether the time of day of exercise training (morning vs evening) would modulate the effects of consumption of a high-fat diet (HFD) on glycaemic control, whole-body health markers and serum metabolomics. METHODS: In this three-armed parallel-group randomised trial undertaken at a university in Melbourne, Australia, overweight/obese men consumed an HFD (65% of energy from fat) for 11 consecutive days. Participants were recruited via social media and community advertisements. Eligibility criteria for participation were male sex, age 30-45 years, BMI 27.0-35.0 kg/m2 and sedentary lifestyle. The main exclusion criteria were known CVD or type 2 diabetes, taking prescription medications, and shift-work. After 5 days, participants were allocated using a computer random generator to either exercise in the morning (06:30 hours), exercise in the evening (18:30 hours) or no exercise for the subsequent 5 days. Participants and researchers were not blinded to group assignment. Changes in serum metabolites, circulating lipids, cardiorespiratory fitness, BP, and glycaemic control (from continuous glucose monitoring) were compared between groups. RESULTS: Twenty-five participants were randomised (morning exercise n = 9; evening exercise n = 8; no exercise n = 8) and 24 participants completed the study and were included in analyses (n = 8 per group). Five days of HFD induced marked perturbations in serum metabolites related to lipid and amino acid metabolism. Exercise training had a smaller impact than the HFD on changes in circulating metabolites, and only exercise undertaken in the evening was able to partly reverse some of the HFD-induced changes in metabolomic profiles. Twenty-four-hour glucose concentrations were lower after 5 days of HFD compared with the participants' habitual diet (5.3 ± 0.4 vs 5.6 ± 0.4 mmol/l, p = 0.001). There were no significant changes in 24 h glucose concentrations for either exercise group but lower nocturnal glucose levels were observed in participants who trained in the evening, compared with when they consumed the HFD alone (4.9 ± 0.4 vs 5.3 ± 0.3 mmol/l, p = 0.04). Compared with the no-exercise group, peak oxygen uptake improved after both morning (estimated effect 1.3 ml min-1 kg-1 [95% CI 0.5, 2.0], p = 0.003) and evening exercise (estimated effect 1.4 ml min-1 kg-1 [95% CI 0.6, 2.2], p = 0.001). Fasting blood glucose, insulin, cholesterol, triacylglycerol and LDL-cholesterol concentrations decreased only in participants allocated to evening exercise training. There were no unintended or adverse effects. CONCLUSIONS/INTERPRETATION: A short-term HFD in overweight/obese men induced substantial alterations in lipid- and amino acid-related serum metabolites. Improvements in cardiorespiratory fitness were similar regardless of the time of day of exercise training. However, improvements in glycaemic control and partial reversal of HFD-induced changes in metabolic profiles were only observed when participants exercise trained in the evening. TRIAL REGISTRATION: anzctr.org.au registration no. ACTRN12617000304336. FUNDING: This study was funded by the Novo Nordisk Foundation (NNF14OC0011493).

Skeletal Muscle Adaptive Responses to Different Types of Short-Term Exercise Training and Detraining in Middle-Age Men.

INTRODUCTION: Whether short-term, single-mode exercise training can improve physical fitness before a period of reduced physical activity (e.g., postsurgery recovery) is not well characterized in clinical populations or middle-age adults. We investigated skeletal muscle adaptive responses after endurance exercise training (ENT), high-intensity interval training (HIIT), or resistance exercise training (RET), and a subsequent period of detraining, in sedentary, middle-age men. METHODS: Thirty-five sedentary men (39 ± 3 yr) were randomized to parallel groups and undertook 6 wk of either ENT (n = 12), HIIT (n = 12), or RET (n = 11) followed by 2.5 wk of detraining. Skeletal muscle fiber characteristics, body composition, muscle thickness, muscle strength, aerobic capacity, resting energy expenditure, and glucose homeostasis were assessed at baseline, and after exercise training and detraining. RESULTS: Lean mass increased after RET and HIIT (+3.2% ± 1.6% and +1.6% ± 2.1%, P < 0.05). Muscle strength (sum of leg press, leg extension, and bench press one-repetition maximums) increased after all training interventions (RET, +25% ± 5%; HIIT, +10% ± 5%; ENT, +7% ± 7%; P < 0.05). Aerobic capacity increased only after HIIT and ENT (+14% ± 7% and +11% ± 11%, P < 0.05). Type I and II muscle fiber size increased for all groups after training (main effect of time, P < 0.05). After a period of detraining, the gains in lean mass and maximal muscle strength were maintained in the RET and HIIT groups, but maximal aerobic capacity declined below posttraining levels in HIIT and ENT (P < 0.05). CONCLUSIONS: Six weeks of HIIT induced widespread adaptations before detraining in middle-age men. Exercise training-induced increases in aerobic capacity declined during 2.5 wk of detraining, but gains in lean mass and muscle strength were maintained.

Lower nocturnal blood glucose response to a potato-based mixed evening meal compared to rice in individuals with type 2 diabetes.

BACKGROUND & AIMS: Guidelines for reducing postprandial blood glucose concentrations include avoiding high glycemic index (GI) foods, such as white potatoes. However, GI testing is often undertaken in the morning with foods consumed in isolation by non-clinical cohorts. We investigated the impact of potato preparation and consumption as part of a mixed-evening meal on postprandial and nocturnal glycemic responses, and postprandial insulin response, in individuals with Type 2 Diabetes Mellitus (T2DM). METHODS: In a randomized, cross-over design, 24 males and females (age 58.3 ± 9.3 y; BMI: 31.7 ± 6.8 kg/m2) with T2DM (diet or metformin controlled) completed four experimental trials after consuming a standardized breakfast (25% daily energy intake (EI)) and lunch (35% EI). Dinner (40% EI) was consumed at 1800 h being either: 1) boiled potato (BOIL); 2) roasted potato (ROAST); 3) boiled potato cooled for 24 h (COOLED); or 4) basmati rice (CONTROL). Each meal contained 50% carbohydrate, 30% fat and 20% protein. Blood samples were collected prior to, immediately post meal and at 30-min intervals for a further 120 min. A continuous glucose monitor was worn to assess nocturnal interstitial glucose concentrations. RESULTS: No differences were detected in postprandial venous glucose area under the curve (iAUC) between CONTROL and all three potato conditions. Postprandial insulin iAUC was greater following COOLED compared to CONTROL (P = 0.003; 95% CI: 18.9-111.72 miU/mL). No significant differences between CONTROL and BOIL or ROAST were detected for postprandial insulin concentrations. All potato meals resulted in lower nocturnal glucose AUC than CONTROL (P < 0.001; 95% CI 4.15-15.67 mmol/L x h). CONCLUSION: Compared to an isoenergetic rice meal, boiled, roasted or boiled then cooled potato-based meals were not associated with unfavourable postprandial glucose responses or nocturnal glycemic control, and can be considered suitable for individuals with T2DM when consumed as part of a mixed-evening meal. CLINICAL TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry https://www.anzctr.org.au/, ACTRN 12618000480280.

Time-Restricted Eating as a Nutrition Strategy for Individuals with Type 2 Diabetes: A Feasibility Study.

Individuals with type 2 diabetes (T2D) require a long-term dietary strategy for blood glucose management and may benefit from time-restricted eating (TRE, where the duration between the first and last energy intake is restricted to 8-10 h/day). We aimed to determine the feasibility of TRE for individuals with T2D. Participants with T2D (HbA1c >6.5 to <9%, eating window >12 h/day) were recruited to a pre-post, non-randomised intervention consisting of a 2-week Habitual period to establish baseline dietary intake, followed by a 4-weeks TRE intervention during which they were instructed to limit all eating occasions to between 10:00 and 19:00 h on as many days of each week as possible. Recruitment, retention, acceptability, and safety were recorded throughout the study as indicators of feasibility. Dietary intake, glycaemic control, psychological well-being, acceptability, cognitive outcomes, and physiological measures were explored as secondary outcomes. From 594 interested persons, and 27 eligible individuals, 24 participants enrolled and 19 participants (mean ± SD; age: 50 ± 9 years, BMI: 34 ± 5 kg/m2, HbA1c: 7.6 ± 1.1%) completed the 6-week study. Overall daily dietary intake did not change between Habitual (~8400 kJ/d; 35% carbohydrate, 20% protein, 41% fat, 1% alcohol) and TRE periods (~8500 kJ/d; 35% carbohydrate, 19% protein, 42% fat, 1% alcohol). Compliance to the 9 h TRE period was 72 ± 24% of 28 days (i.e., ~5 days/week), with varied adherence (range: 4-100%). Comparisons of adherent vs. non-adherent TRE days showed that adherence to the 9-h TRE window reduced daily energy intake through lower absolute carbohydrate and alcohol intakes. Overall, TRE did not significantly improve measures of glycaemic control (HbA1c -0.2 ± 0.4%; p = 0.053) or reduce body mass. TRE did not impair or improve psychological well-being, with variable effects on cognitive function. Participants described hunger, daily stressors, and emotions as the main barriers to adherence. We demonstrate that 4-weeks of TRE is feasible and achievable for these individuals with T2D to adhere to for at least 5 days/week. The degree of adherence to TRE strongly influenced daily energy intake. Future trials may benefit from supporting participants to incorporate TRE in regular daily life and to overcome barriers to adherence.

Author Correction: Time-restricted feeding alters lipid and amino acid metabolite rhythmicity without perturbing clock gene expression.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Time-restricted feeding alters lipid and amino acid metabolite rhythmicity without perturbing clock gene expression.

Time-restricted feeding (TRF) improves metabolism independent of dietary macronutrient composition or energy restriction. To elucidate mechanisms underpinning the effects of short-term TRF, we investigated skeletal muscle and serum metabolic and transcriptomic profiles from 11 men with overweight/obesity after TRF (8 h day-1) and extended feeding (EXF, 15 h day-1) in a randomised cross-over design (trial registration: ACTRN12617000165381). Here we show that muscle core clock gene expression was similar after both interventions. TRF increases the amplitude of oscillating muscle transcripts, but not muscle or serum metabolites. In muscle, TRF induces rhythmicity of several amino acid transporter genes and metabolites. In serum, lipids are the largest class of periodic metabolites, while the majority of phase-shifted metabolites are amino acid related. In conclusion, short-term TRF in overweight men affects the rhythmicity of serum and muscle metabolites and regulates the rhythmicity of genes controlling amino acid transport, without perturbing core clock gene expression.

A Delayed Morning and Earlier Evening Time-Restricted Feeding Protocol for Improving Glycemic Control and Dietary Adherence in Men with Overweight/Obesity: A Randomized Controlled Trial.

We determined the effects of time-restricted feeding (TRF; 8 h/d) versus extended feeding (EXF; 15 h/d) on 24-h and postprandial metabolism and subjective opinions of TRF in men with overweight/obesity. In a randomized crossover design, 11 sedentary males (age 38 ± 5 y; BMI: 32.2 ± 2.0 kg/m2) completed two isoenergetic diet protocols for 5 days, consuming meals at 1000, 1300 and 1700 h (TRF) or 0700, 1400 and 2100 h (EXF). On Day 5, participants remained in the laboratory for 24 h, and blood samples were collected at hourly (0700-2300 h) then 2-hourly (2300-0700 h) intervals for concentrations of glucose, insulin and appetite/incretin hormones. Structured qualitative interviews were conducted following completion of both dietary conditions and investigated thematically. Total 24-h area under the curve (AUCtotal) [glucose] tended to be lower for TRF versus EXF (-5.5 ± 9.0 mmol/L/h, P = 0.09). Nocturnal glucose AUC was lower in TRF (-4.2 ± 5.8 mmol/L/h, P = 0.04), with no difference in waking glucose AUC or AUCtotal for [insulin]. Attitudes towards TRF were positive with improved feelings of well-being. Barriers to TRF were work schedules, family commitments and social events. Compared to extended feeding, short-term TRF improved nocturnal glycemic control and was positively perceived in men with overweight/obesity.

Dietary intakes of professional Australian football league women's (AFLW) athletes during a preseason training week.

OBJECTIVES: In 2016 the Australian football league introduced the first women's league, integrating part-time female athletes into the professional sporting environment. This study aims to assess the dietary intakes of professional Australian football league women's (AFLW) athletes to highlight key focus areas for nutrition and additionally provide nutrition recommendations for dietitians working with these athletes. DESIGN: Cross-sectional study. METHODS: Dietary intake data was collected from 23 players from the same club competing in the Australian football league women's, during a preseason week. Dietary intakes were assessed using three day estimated food records. RESULTS: Majority of athletes did not meet recommendations for carbohydrate (96%, n=22), iron (87%, n=20) and calcium (61%, n=14). In comparison, majority of athletes met protein (74%, n=17) and fat (78%, n=18) recommendations. No significant difference was found in energy intake on main training, light training and recovery days (p>0.05). Energy and carbohydrate intakes reported by AFLW athletes (1884±457kcalday-1 and 2.7±0.7gkg-1day-1) were consistent with values reported in previous studies that included professional female athletes. CONCLUSIONS: This research highlights that further exploration of the factors that influence dietary intake is required to support athletes to meet energy and carbohydrate recommendations required for desired training and performance outcomes.

Dietary Intakes of Professional and Semi-Professional Team Sport Athletes Do Not Meet Sport Nutrition Recommendations-A Systematic Literature Review.

Background: to develop sport-specific and effective dietary advice, it is important to understand the dietary intakes of team sport athletes. This systematic literature review aims to (1) assess the dietary intakes of professional and semi-professional team sport athletes and (2) to identify priority areas for dietetic intervention. METHODS: an extensive search of MEDLINE, Sports DISCUS, CINAHL, Web of Science, and Scopus databases in April-May 2018 was conducted and identified 646 studies. Included studies recruited team sport, competitive (i.e. professional or semi-professional) athletes over the age of 18 years. An assessment of dietary intake in studies was required and due to the variability of data (i.e. nutrient and food group data) a meta-analysis was not undertaken. Two independent authors extracted data using a standardised process. RESULTS: 21 (n = 511) studies that assessed dietary intake of team sport athletes met the inclusion criteria. Most reported that professional and semi-professional athletes' dietary intakes met or exceeded recommendations during training and competition for protein and/or fat, but not energy and carbohydrate. Limitations in articles include small sample sizes, heterogeneity of data and existence of underreporting. CONCLUSIONS: this review highlights the need for sport-specific dietary recommendations that focus on energy and carbohydrate intake. Further exploration of factors influencing athletes' dietary intakes including why athletes' dietary intakes do not meet energy and/or carbohydrate recommendations is required.

Between-meal sucrose-sweetened beverage consumption impairs glycaemia and lipid metabolism during prolonged sitting: A randomized controlled trial.

BACKGROUND & AIMS: Chronic overconsumption of sugar-sweetened beverages (SSBs) is associated with unfavourable health effects, including promotion of obesity. However, the acute effects of consuming SSBs on glucose and lipid metabolism remain to be characterized in a real-world, post-prandial context of prolonged sitting. We quantified the acute effects of between-meal SSB consumption compared with water, on glucose and lipid metabolism in habitual soft drink consumers during prolonged sitting. METHODS: Twenty-eight overweight or obese young adults [15 males; 23 ± 3 (mean ± SD) years, body mass index (BMI) 31.0 ± 3.6 kg/m2) participated. During uninterrupted sitting and following standardized breakfast and lunch meals, each participant completed two 7-h conditions on separate days in a randomized, crossover design study. For each condition, participants consumed either a sucrose SSB or water mid-morning and mid-afternoon. Peak responses and total area under the curve (tAUC) over 7 h for blood glucose, insulin, C-peptide, triglyceride and non-esterified fatty acid (NEFA) concentrations were quantified and compared. RESULTS: Compared to water, SSB consumption significantly increased the peak responses for blood glucose (20 ± 4% (mean ± SEM)), insulin (43 ± 15%) and C-peptide (21 ± 6%) concentrations. The tAUC for all these parameters was also increased by SSB consumption. The tAUC for triglycerides was 15 ± 5% lower after SSBs and this was driven by males (P < 0.05), as females showed no difference between conditions. The tAUC for NEFAs was 13 ± 5% lower after the SSB condition (P < 0.05). CONCLUSIONS: Between-meal SSB consumption significantly elevated plasma glucose responses, associated with a sustained elevation in plasma insulin throughout a day of prolonged sitting. The SSB-induced reduction in circulating triglycerides and NEFAs indicates significant modulation of lipid metabolism, particularly in males. These metabolic effects may contribute to the development of metabolic disease when SSB consumption is habitual and co-occurring with prolonged sitting. Clinical Trial Registry number: ACTRN12616000840482, https://anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12616000840482.