Publications by authors named "Louise H Naylor"

This narrative review highlights the degree to which new antiobesity medications based on gut-derived nutrient-stimulated hormones (incretins) cause loss of lean mass, and the importance of resistance exercise to preserve muscle. Glucagon-like peptide 1 receptor agonists (GLP-1RA) induce substantial weight loss in randomized trials, effects that may be enhanced in combination with glucose-dependent insulinotropic polypeptide (GIP) receptor agonists. Liraglutide and semaglutide (GLP-1RA), tirzepatide (GLP-1 and GIP receptor dual agonist), and retatrutide (GLP-1, GIP, and glucagon receptor triple agonist) are peptides with incretin agonist activity that induce ∼15-24% weight loss in adults with overweight and obesity, alongside beneficial impacts on blood pressure, cholesterol, blood glucose, and insulin.

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Background: Based on the largely untested premise that it is a restorative hormone that may reverse the detrimental impacts of aging, prescription of testosterone (T) has increased in recent decades despite no new clinical indications. It is apparent that middle-aged and older men with low-normal serum T levels are considering T supplementation as an anti-aging strategy. At the same time, there is evidence that physical activity (PA) is at historical lows in the Western world.

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Biological sex is a salient factor in exercise-induced vascular adaptation. Although a male bias is apparent in the literature, the methodological quality of available studies in females is not yet known. This systematic review with narrative synthesis aimed to assess available evidence of exercise interventions on endothelial function, measured using flow-mediated dilation, in otherwise healthy individuals and athletes.

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Few training studies have assessed the impact of different modes of exercise on changes in cardiac function. This study investigated changes in left ventricular (LV) systolic and diastolic function following endurance (END) and resistance (RES) training in healthy participants. Sixty-four individuals participated in a randomized crossover design trial, involving 12 wk of END and RES training, separated by a 12-wk washout.

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Introduction: Exercise improves vascular function, but it is unclear whether benefits are mediated by traditional cardiovascular risk factors or whether sex differences in training effects exist in older adults. We hypothesized that exercise would improve cardiovascular risk factors, that males and females would benefit similarly, and that improvements in risk factors would correlate with changes in vascular function.

Methods: Seventy-two healthy middle-aged/older adults (age, 62 ± 7 yr; 26%♂) were randomized to a land-walking ( n = 23), water-walking ( n = 25), or a nonexercise control group (C; n = 23).

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Purpose: Recent studies suggest that episodic increases in cerebral blood flow (CBF) may contribute to the improvement in brain health associated with exercise training. Optimising CBF during exercise may enhance this benefit. Water immersion in ~ 30-32 °C augments CBF at rest and during exercise; however, the impact of water temperature on the CBF response has not been investigated.

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Background: Physical activity reduces cardiovascular risk, partly via direct effects on the arterial wall. We hypothesized that vascular function responses would be modality-specific, sex-dependent, and express a high degree of heritability.

Methods: We recruited 90 same-sex twins (31 monozygotic, 14 dizygotic dizygotic pairs; 25.

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Middle-aged and older men have typically accumulated comorbidities, are increasingly sedentary, and have lower testosterone concentrations (T) compared to younger men. Reduced physical activity (PA) and lower T both are associated with, and may predispose to, metabolically adverse changes in body composition, which contribute to higher risks of cardiometabolic disease. Exercise improves cardiometabolic health, but sustained participation is problematic.

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Flow-mediated dilation (FMD) provides a valid bioassay of vascular function in humans. Although water immersion induces hemodynamic effects that modify brachial artery shear stress, it is unclear whether water-based exercise modifies FMD. We hypothesized that exercise in 32°C water would decrease brachial artery shear and FMD relative to land-based exercise, whereas exercise in 38°C would increase brachial shear and FMD.

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This study compared differences in cardiovascular (CV) risk factor responses between males and females following endurance (END) and resistance (RES) training. We present the frequency of responders to each training modality and the magnitude of response. Using a randomized crossover design, 68 healthy adults [age: female (F): 24.

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Background: Individual variability in traditional cardiovascular risk factor responses to different exercise modalities has not been directly addressed in humans using a randomized cross-over design.

Methods: Body weight and body mass index, resting blood pressure, blood glucose, insulin and lipids were assessed in 68 healthy untrained adults (26±6 years) who underwent three-months of exercise training targeted at improving cardiopulmonary fitness (endurance) and skeletal muscle function (resistance), separated by three-months washout.

Results: There were significant increases in weight and body mass index following resistance (+0.

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Heart failure (HF) is characterised by abnormal conduit and resistance artery function in humans. Microvascular function in HF is less well characterised, due in part to the lack of tools to image these vessels in vivo. The skin microvasculature is a surrogate for systemic microvascular function and health and plays a key role in thermoregulation, which is dysfunctional in HF.

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We studied monozygotic (MZ) and dizygotic (DZ) twin pairs following resistance (RES) and endurance (END) training to assess genetic and environmental contributions to cerebrovascular function. Cerebrovascular function (rest, autoregulation, hypercapnia, exercise) was assessed in 86 healthy same-sex MZ (30 pairs) and DZ (13 pairs) twins, who underwent 3 months of END and RES. Carbon dioxide ( ), mean arterial pressure (MAP) and middle cerebral artery velocity (MCAv) were measured and MCAv resistance (MCA ) was calculated.

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Purpose: Changes in left ventricular mass (LVM) and end-diastolic volume (EDV) in response to exercise training are important determinants of functional capacity in health and disease, but the impact of different exercise modalities remains unclear.

Methods: Using a randomized crossover design we studied the impact of resistance (RES) and endurance (END) training using cardiac magnetic resonance imaging in previously untrained monozygotic (MZ) and dizygotic (DZ) twin pairs (n = 72; 22 MZ pairs, 14 DZ same-sex pairs; 26.1 ± 5.

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Article Synopsis
  • The UK is experiencing population growth and an increase in inactivity and health issues, highlighting the need for better exercise interventions to enhance health and reduce healthcare costs.
  • Current exercise strategies often rely on a 'one-size-fits-all' approach that doesn't provide significant health benefits, especially for those with chronic conditions.
  • The proposal recommends establishing a clinical exercise physiology profession in the UK, similar to successful models in Australia, with accredited professionals trained to offer personalized exercise prescriptions and support behavioral changes in physical activity.
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It is generally considered that regular exercise maintains brain health and reduces the risk of cerebrovascular diseases such as stroke and dementia. Since the benefits of different "types" of exercise are unclear, we sought to compare the impacts of endurance and resistance training on cerebrovascular function. In a randomized and crossover design, 68 young healthy adults were recruited to participate in 3 mo of resistance and endurance training.

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Purpose: No previous study has described sex differences in chronic cardiac adaptation in response to distinct modalities of exercise training in humans.

Methods: Cardiac magnetic resonance imaging (1.5 T) was used to assess left ventricular (LV) outcomes in 78 untrained subjects (46F, 26 M; 26.

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Article Synopsis
  • The study involved 63 older adults undergoing either land walking, water walking, or no exercise for 24 weeks to explore how exercise affects blood flow in the brain.
  • Results showed no significant changes in overall blood flow velocities or neurovascular coupling for either exercise group, although water walking improved cerebral autoregulation slightly.
  • The findings suggest that while exercise doesn't result in major changes in cerebrovascular function, it may lead to modest improvements and highlights the need for more research into exercise's long-term effects on brain health.
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Objectives: Exercise places physiological demands upon the cardiovascular system, subsequently leading to adaptations in structure and function. Different exercise modalities (endurance, strength and power) lead to distinct hemodynamic demands and, possibly, different patterns of adaptation. Our aim was to assess and compare brachial and femoral artery function and structure in elite level athletes engaged in endurance, strength and power sports.

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As men age, serum testosterone (T) concentrations decrease, as do fitness, strength, and lean mass. Whether testosterone treatment confers additive benefit to reverse these changes when combined with exercise training in middle-to-older aged men remains unclear. We assessed the effects of T treatment and exercise, alone and in combination, on aerobic capacity (V̇opeak), body composition, and muscular strength in men 50-70 yr, waist circumference ≥95 cm and low-normal serum T (6-14 nmol·L).

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Introduction: Exercise training has antiatherogenic effects on conduit and resistance artery function and structure in humans and induces angiogenic changes in skeletal muscle. However, training-induced adaptation in cutaneous microvessels is poorly understood, partly because of technological limitations. Optical coherence tomography (OCT) is a novel high-resolution imaging technique capable of visualizing cutaneous microvasculature at a resolution of ~30 μm.

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Context: With age, testosterone (T) and physical activity levels often decline in parallel. The effect of combining T treatment and exercise training on ambulatory blood pressure (ABP) is unclear.

Objective: To assess T and exercise effects, alone and in combination, on ABP in men aged 50-70 years, waist circumference ≥ 95 cm and low-normal serum T (6-14 nmol/L), without organic hypogonadism.

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Background: Epidemiological studies have reported lower risk of cardiovascular disease with moderate coffee consumption. In addition, emerging evidence indicates that consumption of coffee beverages enriched in chlorogenic acids (CGAs) may influence blood pressure and endothelial function, suggesting that the beneficial cardiovascular effect of coffee may relate to its CGA content.

Objectives: We conducted a double-blind randomized crossover trial to test the effect of acute consumption of a decaffeinated green coffee extract (DGCE), rich in CGAs, on endothelial function in healthy subjects.

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Background: Postprandial glucose, insulin, and triglyceride metabolism is impaired by prolonged sitting, but enhanced by exercise. The aim of this study was to assess the effects of a continuous exercise bout with and without intermittent active interruptions to prolonged sitting on postprandial glucose, insulin, and triglycerides.

Methods: Sedentary adults who were overweight to obese (n = 67; mean age 67 yr SD ± 7; BMI 31.

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