Publications by authors named "John Hawley"

Aims: Investigate the effects of breakfast timing on postprandial glycaemia in adults with type 2 diabetes (T2D), and the impact of a 20-min walk after breakfast.

Methods: Eleven adults with T2D (57 ± 7 y; HbA1c 7.4 ± 1%) participated in a six-week randomised crossover controlled trial comprising three 4-day conditions: Early (0700 h), Mid (0930 h) and Delayed (1200 h).

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This article provides a recap of the 10 Questions/10 Experts session at the 2024 American College of Sports Medicine Annual Meeting. Each of the speakers considered the validity of common "myths," while providing evidence-based opinions to support, or, bust, myths addressing the following questions: (1) Would 100 g/hr of carbohydrate be advisable for the Olympic Cycling Road race? (2) Is there an advantage in the marathon of ingesting bicarbonate as a hydrogel product? (3) Can genotyping be used to individualize caffeine supplementation in football? (4) Should low fluid consumers drink more to improve 1,500-m track performance? (5) Do urinary markers of dehydration predict poor basketball performance? (6) Do placebo effects influence 10-km track performance? (7) Should combat athletes make weight using glucagon-like peptide-1 receptor agonists? (8) Would crushed ice ingestion help tennis umpires make better decisions in the heat? (9) Are collagen supplements useful to reduce tendon and ligament injuries in volleyball? and (10) Should female athletes plan their training and diet according to their menstrual cycle? This article describes the content of each of the presentations including the most important outcomes and conclusions drawn by the presenters.

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Background: Intermittent fasting (IF) is an effective energy restricted dietary strategy to reduce body and fat mass and improve metabolic health in individuals with either an overweight or obese status. However, dietary energy restriction may impair muscle protein synthesis (MPS) resulting in a concomitant decline in lean body mass. Due to periods of prolonged fasting combined with irregular meal intake, we hypothesised that IF would reduce rates of MPS compared to an energy balanced diet with regular meal patterns.

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Aims: To test the efficacy of time-restricted eating (TRE) in comparison to dietitian-led individualised dietary guidance to improve HbA1c in people with Type 2 diabetes mellitus.

Methods: In a parallel groups design, 51 adults (35-65 y) with Type 2 diabetes mellitus and overweight/obesity (HbA1c ≥6.5% (48 mmol/mol), BMI ≥25-≤40 kg/m) commenced a six-month intervention.

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Article Synopsis
  • The Olympic Games showcase the top athletes, whose extraordinary abilities in speed, strength, and endurance are often overlooked by casual fans.
  • Endurance running, especially the marathon, allows for a unique comparison between elite and recreational runners, highlighting their vastly different experiences and physiological demands.
  • The review emphasizes the biological advantages of elite athletes and discusses inconsistencies in sports science communication regarding the differences between top competitors and well-trained recreational runners.
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  • Time-restricted eating (TRE) is a dietary strategy that limits daily eating to a specific time window, and this study aimed to see if it works for pregnant individuals at risk of gestational diabetes mellitus (GDM).
  • In a 5-week trial, 32 pregnant participants either followed TRE (10-hour eating window) or usual care, with no significant differences found in glycemic control, body composition, or blood pressure between the two groups.
  • While participants on TRE successfully decreased their eating window and reported increased hunger in the evening, the intervention had minimal impact on their overall diet and health outcomes.
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Background: Time restricted eating (TRE) is a dietary strategy that may improve metabolic health. However, no studies have compared TRE with current practice (CP) in dietetics.

Hypothesis: TRE will not be inferior to CP to improve glycaemic control in individuals at risk of type 2 diabetes (T2D).

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The age-related loss of skeletal muscle mass and physical function leads to a loss of independence and an increased reliance on health-care. Mitochondria are crucial in the aetiology of sarcopenia and have been identified as key targets for interventions that can attenuate declines in physical capacity. Exercise training is a primary intervention that reduces many of the deleterious effects of ageing in skeletal muscle quality and function.

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Muscle isometric torque fluctuates according to time-of-day with such variation owed to the influence of circadian molecular clock genes. Satellite cells (SCs), the muscle stem cell population, also express molecular clock genes with several contractile-related genes oscillating in a diurnal pattern. Currently, limited evidence exists regarding the relationship between SCs and contractility, although long-term SC ablation alters muscle contractile function.

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Exercise perturbs energy homeostasis in skeletal muscle and engages integrated cellular signalling networks to help meet the contraction-induced increases in skeletal muscle energy and oxygen demand. Investigating exercise-associated perturbations in skeletal muscle signalling networks has uncovered novel mechanisms by which exercise stimulates skeletal muscle mitochondrial biogenesis and promotes whole-body health and fitness. While acute exercise regulates a complex network of protein post-translational modifications (e.

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  • Guidelines worldwide endorse exercise as a key treatment for patients with lower extremity peripheral artery disease (PAD).
  • Structured exercise programs yield the best outcomes, and this paper aims to help establish these programs for patients with chronic PAD.
  • It discusses specific exercise protocols, assesses patient outcomes based on evidence, and addresses disparities in access to supervised programs across Europe, pointing out areas needing further research.
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  • Exercise is highly recommended globally as an essential part of managing lower extremity peripheral artery disease (PAD) to improve patient outcomes.
  • This paper aims to help clinicians create effective structured exercise programs tailored for patients with symptomatic chronic PAD, detailing various training protocols and assessment methods.
  • It also addresses the unequal access to supervised exercise programs across Europe and points out the need for more research in this area.
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Article Synopsis
  • Exercise is essential for managing lower extremity peripheral artery disease (PAD), and guidelines worldwide strongly support its use.
  • A structured exercise program is crucial for achieving the best results in patients with symptomatic chronic PAD, with various training protocols outlined.
  • The document also addresses disparities in access to supervised exercise programs in Europe and identifies areas where more research is needed.
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The ability of skeletal muscle to adapt to repeated contractile stimuli is one of the most intriguing aspects of physiology. The molecular bases underpinning these adaptations involve increased protein activity and/or expression, mediated by an array of pre- and post-transcriptional processes, as well as translational and post-translational control. A longstanding dogma assumes a direct relationship between exercise-induced increases in mRNA levels and subsequent changes in the abundance of the proteins they encode.

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Our interest in the genetic basis of skin color variation between populations led us to seek a Native American population with genetically African admixture but low frequency of European light skin alleles. Analysis of 458 genomes from individuals residing in the Kalinago Territory of the Commonwealth of Dominica showed approximately 55% Native American, 32% African, and 12% European genetic ancestry, the highest Native American genetic ancestry among Caribbean populations to date. Skin pigmentation ranged from 20 to 80 melanin units, averaging 46.

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Skeletal muscle comprises approximately 50% of individual body mass and plays vital roles in locomotion, heat production, and whole body metabolic homeostasis. This tissue exhibits a robust diurnal rhythm that is under control of the suprachiasmatic nucleus (SCN) region of the hypothalamus. The SCN acts as a "central" coordinator of circadian rhythms, while cell-autonomous "peripheral" clocks are located within almost all other tissues/organs in the body.

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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.

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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/m) 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.

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Human skeletal muscle demonstrates remarkable plasticity, adapting to numerous external stimuli including the habitual level of contractile loading. Accordingly, muscle function and exercise capacity encompass a broad spectrum, from inactive individuals with low levels of endurance and strength to elite athletes who produce prodigious performances underpinned by pleiotropic training-induced muscular adaptations. Our current understanding of the signal integration, interpretation, and output coordination of the cellular and molecular mechanisms that govern muscle plasticity across this continuum is incomplete.

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Objective: This study aimed to assess the impact of time-restricted eating (TRE) on integrated skeletal muscle myofibrillar protein synthesis (MyoPS) rates in males with overweight/obesity.

Methods: A total of 18 healthy males (age 46 ±  5 years; BMI: 30 ± 2 kg/m ) completed this exploratory, parallel, randomized dietary intervention after a 3-day lead-in diet. Participants then consumed an isoenergetic diet (protein: ~1.

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Levels of obesity and overweight are increasing globally, with affected individuals often experiencing health issues and reduced quality of life. The pathogenesis of obesity is complex and multifactorial, and effective solutions have been elusive. In this Viewpoint, experts in the fields of medical therapy, adipocyte biology, exercise and muscle, bariatric surgery, genetics, and public health give their perspectives on current and future progress in addressing the rising prevalence of obesity.

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There currently exists a modern epidemic of sleep loss, triggered by the changing demands of our 21st century lifestyle that embrace 'round-the-clock' remote working hours, access to energy-dense food, prolonged periods of inactivity, and on-line social activities. Disturbances to sleep patterns impart widespread and adverse effects on numerous cells, tissues, and organs. Insufficient sleep causes circadian misalignment in humans, including perturbed peripheral clocks, leading to disrupted skeletal muscle and liver metabolism, and whole-body energy homeostasis.

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Diet modification and exercise training are primary lifestyle strategies for obesity management, but poor adherence rates limit their effectiveness. Time-restricted eating (TRE) and high-intensity interval training (HIIT) improve cardiometabolic health in at-risk individuals, but whether these two interventions combined induce superior improvements in glycemic control than each individual intervention is not known. In this four-armed randomized controlled trial (ClinicalTrials.

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Introduction: DNA methylation regulates exercise-induced changes in the skeletal muscle transcriptome. However, the specificity and the time course responses in the myogenic regulatory factors DNA methylation and mRNA expression after divergent exercise modes are unknown.

Purpose: This study aimed to compare the time course changes in DNA methylation and mRNA expression for selected myogenic regulatory factors ( MYOD1 , MYF5 , and MYF6 ) immediately after, 4 h after, and 8 h after a single bout of resistance exercise (RE), high-intensity interval exercise (HIIE), and concurrent exercise (CE).

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