Publications by authors named "Noakes T"

Very-low-carbohydrate diets (LCHF; <50g/day) have been debated for their potential to lower pre-exercise muscle and liver glycogen stores and metabolic efficiency, risking premature fatigue. It is also hypothesized that carbohydrate ingestion during prolonged exercise delays fatigue by increasing carbohydrate oxidation, thereby sparing muscle glycogen. Leveraging a randomized crossover design, we evaluated performance during strenuous time-to-exhaustion (70%⩒O) tests in trained triathletes following 6-week high-carbohydrate (HCLF, 380g/day) or very-low-carbohydrate (LCHF, 40g/day) diets to determine (i) if adoption of the LCHF diet impairs time-to-exhaustion performance, (ii) whether carbohydrate ingestion (10g/hour) 6-12x lower than current CHO fuelling recommendations during low glycogen availability (>15-hour pre-exercise overnight fast and/or LCHF diet) improves time-to-exhaustion by preventing exercise-induced hypoglycemia (EIH; <3.

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Oxide-free surfaces of polycrystalline Cu are prepared using acetic acid etching after chemical-mechanical polishing. UV ozone treatment is shown to increase the work function of the cleaned Cu by up to 0.5 eV.

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Introduction: Menopause is a key workplace issue. Many women will experience symptoms through their later working life. The ambulance service constitutes an employment setting that, dependent on the roles of female staff, can impact on the severity of menopause symptoms and experiences (Prothero et al.

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Introduction: This article reports the evaluation of a personalized, team-based comprehensive lifestyle modification program targeting known triggers of hyperinsulinemia and insulin resistance.

Methods: A retrospective chart review was undertaken for 536 participants in a novel high-intensity lifestyle behavioral modification program. Surrogate markers of insulin resistance and metabolic syndrome‒related pathologies were measured before and after participation in the the program.

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Background: In spite of infants and children aged 0-5 years experiencing mental health difficulties being estimated to be in the range of 6%-18% globally, the mental health care needs for this age group are often overlooked in the design of specialist mental health services. Although there is increasing recognition of the importance of infant mental health services and treatments for younger children, access remains a barrier. Mental health services specifically designed for children 0-5 years are vital; however, little is known about how these services ensure access for infants at risk of mental health difficulties and their families.

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Recently we reported similar performances in both progressive tests to exhaustion (VOmax) and 5km running time trials (5KTT) after consuming low-carbohydrate, high-fat (LCHF) or high-carbohydrate, low-fat (HCLF) diets. Accordingly, we tested the null hypothesis that the metabolic responses during both tests would be similar across diets. In a randomized, counterbalanced, cross-over design, seven male athletes (VOmax: 61.

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In exercise science, the crossover effect denotes that fat oxidation is the primary fuel at rest and during low-intensity exercise with a shift towards an increased reliance on carbohydrate oxidation at moderate to high exercise intensities. This model makes four predictions: First, >50% of energy comes from carbohydrate oxidation at ≥60% of maximum oxygen consumption (VOmax), termed the crossover point. Second, each individual has a maximum fat oxidation capacity (FATMAX) at an exercise intensity lower than the crossover point.

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High carbohydrate, low fat (HCLF) diets have been the predominant nutrition strategy for athletic performance, but recent evidence following multi-week habituation has challenged the superiority of HCLF over low carbohydrate, high fat (LCHF) diets, along with growing interest in the potential health and disease implications of dietary choice. Highly trained competitive middle-aged athletes underwent two 31-day isocaloric diets (HCLF or LCHF) in a randomized, counterbalanced, and crossover design while controlling calories and training load. Performance, body composition, substrate oxidation, cardiometabolic, and 31-day minute-by-minute glucose (CGM) biomarkers were assessed.

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The minimum achievable particle beam emittance in an electron accelerator depends strongly on the intrinsic emittance of the photocathode electron source. This is measurable as the mean longitudinal and transverse energy spreads in the photoemitted electron beam (MLE and MTE respectively); consequently, MLE and MTE are notable figures of merit for photocathodes used as electron sources in particle accelerators. The overall energy spread is defined by the sum of the MTE and the MLE, and the minimization of MTE is crucial to reduce emittance and thus generate a high-brightness electron beam.

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Purpose: To continuously measure body core temperature (Tc) throughout a mass-participation ultramarathon in subelite recreational runners to quantify Tc magnitude and the influence of aerobic fitness and body fat.

Methods: Twenty-three participants (19 men and 4 women; age 45 [9] y; body mass 72.0 [9.

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A growing number of endurance athletes have considered switching from a traditional high-carbohydrate/low-fat (HCLF) to a low-carbohydrate/high-fat (LCHF) eating pattern for health and performance reasons. However, few studies have examined how LCHF diets affect blood lipid profiles in highly-trained runners. In a randomized and counterbalanced, cross-over design, athletes (n = 7 men; VO2max: 61.

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The introduction of the needle muscle biopsy technique in the 1960s allowed muscle tissue to be sampled from exercising humans for the first time. The finding that muscle glycogen content reached low levels at exhaustion suggested that the metabolic cause of fatigue during prolonged exercise had been discovered. A special pre-exercise diet that maximized pre-exercise muscle glycogen storage also increased time to fatigue during prolonged exercise.

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Objective: To investigate whether a cycling test based on decremental loads (DEC) could elicit higher maximal oxygen uptake (V˙O2max) values compared with an incremental test (INC).

Design: Nineteen well-trained individuals performed an INC and a DEC test on a single day, in randomized order.

Methods: During INC, the load was increased by 20 W·min-1 until task failure.

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The Women's Health Initiative Randomized Controlled Dietary Modification Trial (WHIRCDMT) was designed to test whether the US Department of Agriculture's 1977 Dietary Guidelines for Americans protects against coronary heart disease (CHD) and other chronic diseases. The only significant finding in the original 2006 WHIRCDMT publication was that postmenopausal women with CHD randomised to a low-fat 'heart-healthy' diet in 1993 were at 26% greater risk of developing additional CHD events compared with women with CHD eating the control diet. A 2017 WHIRCDMT publication includes data for an additional 5 years of follow-up.

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Purpose: This study aimecd to investigate whether elite athletes could reach higher values of maximal oxygen uptake (V˙O2max) during a decremental exercise test in comparison with a traditional incremental test, as recently demonstrated in trained individuals.

Methods: Nine male runners (age 25.8 [5.

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The shift of academic discourse to an online space without guardians gives motivated academic cyberbullies an opportunity to harass susceptible recipients. Cyberbullying by higher education employees is a neglected phenomenon; despite the dangers it poses to academic free speech as well as other negative outcomes. In the absence of an adequate definition for Online Academic Bullying (OAB) as a surfacing threat, its' targets cannot readily gauge its severity or confidently report that they are victims.

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The kinetics of recovery from neuromuscular fatigue resulting from exercise time trials (TTs) of different durations are not well-known. The aim of this study was to determine if TTs of three different durations would result in different short-term recovery in maximal voluntary contraction (MVC) and evoked peak forces. Twelve trained subjects performed repetitive concentric right knee extensions on an isokinetic dynamometer self-paced to last 3, 10, and 40 min (TTs).

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Very little is known about how long-term (>6 months) adaptation to a low-carbohydrate, high-fat (LCHF) diet affects insulin signaling in healthy, well-trained individuals. This study compared glucose tolerance; skeletal muscle glucose transporter 4 (GLUT4) and insulin receptor substrate 1 (IRS1) content; and muscle enzyme activities representative of the main energy pathways (3-hydroxyacetyl-CoA dehydrogenase, creatine kinase, citrate synthase, lactate dehydrogenase, phosphofructokinase, phosphorylase) in trained cyclists who followed either a long-term LCHF or a mixed-macronutrient (Mixed) diet. On separate days, a 2-hr oral glucose tolerance test was conducted, and muscle samples were obtained from the vastus lateralis of fasted participants.

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A common belief is that high intensity exercise (>60%VO) is best sustained by high rates of carbohydrate oxidation. The belief is based, in part, on an idea developed by Krogh and Lindhard in 1920. In the 100 years since, few studies have tested its validity.

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Background: Low carbohydrate high fat (LCHF) diets are increasing in popularity amongst patients with type 2 diabetes (T2D), however it is unclear what constitutes a sustainable LCHF diet in a real-world setting.

Methods: This descriptive multi-method study characterized the diets, T2D status, and personal experiences of individuals with T2D who claimed to have followed an LCHF diet for at least 6 months. Participants completed a medications history, mixed-method dietary assessment, provided a blood sample, and were interviewed in-depth about their experiences with the diet (First-Assessment).

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Introduction: The brain plays a key role in the perceptual regulation of exercise, yet neuroimaging techniques have only demonstrated superficial brain areas responses during exercise, and little is known about the modulation of the deeper brain areas at different intensities.

Objectives/methods: Using a specially designed functional MRI (fMRI) cycling ergometer, we have determined the sequence in which the cortical and subcortical brain regions are modulated at low and high ratings perceived exertion (RPE) during an incremental exercise protocol.

Results: Additional to the activation of the classical motor control regions (motor, somatosensory, premotor and supplementary motor cortices and cerebellum), we found the activation of the regions associated with autonomic regulation (ie, insular cortex) (ie, positive blood-oxygen-level-dependent (BOLD) signal) during exercise.

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Cricket coaching manuals published after 2009 accept as a norm for batsmen to lift the bat in the direction of the slips. A mixed-methods study conducted among 161 coaches around the world showed that most cricket coaches (83%) coach the straight batting backlift technique (SBBT) as opposed to the lateral batting backlift technique (LBBT) at various proficiency levels of the game. The LBBT (more beneficial for cricket batsmen) is one in which the bat is lifted laterally in the direction of second slip or gully.

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Background: This study aimed primarily to investigate the lateral batting backlift technique (LBBT) among semi-professional, professional and current international cricket players. A key question was to investigate whether this technique is a factor that contributes to success for cricket players at the highest levels of the game.

Methods: The participants in this study's sample (n = 130) were South African semi-professional players (SP) (n = 69), professional players (PP) (n = 49) and South African international professional players (SAI) (n = 12).

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