Global physical fitness (PF) levels have declined over the past 50 years, contributing to early health risks in children although it is still unclear how age, gender and socioeconomic status (SES) impact PF risk. This study aimed to identify unique health risks related to age, SES and gender that might influence muscular fitness (MF) and cardiorespiratory fitness (CRF) levels of primary school children in South Africa. Children ( = 349, boys = 165; girls = 184) of low ( = 201) and high SES ( = 148) underwent three time point measurements at 6, 9 and 12 years spanning seven primary school years.
View Article and Find Full Text PDFBMC Med
December 2023
Background: Preliminary evidence demonstrates some parameters of metabolic control, including glycaemic control, lipid control and insulin resistance, vary across the menstrual cycle. However, the literature is inconsistent, and the underlying mechanisms remain uncertain. This study aimed to investigate the association between the menstrual cycle phase and metabolites and to explore potential mediators and moderators of these associations.
View Article and Find Full Text PDFCyclical changes in hormone profiles across the menstrual cycle are associated with alterations in metabolic control. MicroRNAs (miRNAs) contribute to regulating metabolic control, including adipose tissue metabolism. How fluctuations in hormonal profiles across the menstrual cycle affect adipose tissue miRNA expression remains unknown.
View Article and Find Full Text PDFStudies on adipose tissue are useful in understanding metabolic and other conditions. Human subcutaneous adipose tissue is accessible. With appropriate training and strict adherence to aseptic technique, subcutaneous adipose samples can be safely and efficiently obtained in a non-clinical setting by researchers.
View Article and Find Full Text PDFContext: There is evidence demonstrating variation in insulin sensitivity across the menstrual cycle. However, to date, research has yielded inconsistent results.
Objective: This study investigated variation in insulin sensitivity across the menstrual cycle and associations with body mass index (BMI), physical activity, and cardiorespiratory fitness (CRF).
Understanding human physiological responses to high-fat energy excess (HFEE) may help combat the development of metabolic disease. We aimed to investigate the impact of manipulating the n-3PUFA content of HFEE diets on whole-body and skeletal muscle markers of insulin sensitivity. Twenty healthy males were overfed (150% energy, 60% fat, 25% carbohydrate, 15% protein) for 6 d.
View Article and Find Full Text PDFBackground: School-based physical activity and running programmes, such as The Daily Mile™, are increasing in popularity globally. The aim of this research was to examine the acute impact of such classroom physical activity breaks on cognition and affective wellbeing.
Methods: A total of 5463 school pupils from 332 schools took part in a citizen science project with a repeated measures design.
We thank Daly-Smith et al. for taking the time to read the results of our pilot research study, describing it as an important and welcome contribution. Nonetheless, the authors argue six points against our conclusion.
View Article and Find Full Text PDFBackground: Despite the known benefits of a physically active lifestyle, there are few examples of interventions that have been successfully implemented at a population level over a long period of time. One such example is The Daily Mile, a school based physical activity initiative, where a teacher takes their class out daily during class time for a short bout of ambulatory activity. At one school, this activity appears has been sustained over a long period (6 years), has the whole school participating and is now incorporated into its daily routine.
View Article and Find Full Text PDFBackground: The Daily Mile is a physical activity programme made popular by a school in Stirling, Scotland. It is promoted by the Scottish Government and is growing in popularity nationally and internationally. The aim is that each day, during class time, pupils run or walk outside for 15 min (~1 mile) at a self-selected pace.
View Article and Find Full Text PDFCyclists in the Tour de France are endurance specialists. Twin and family studies have shown that approximately 50% of the variance in a number of performance-related phenotypes (whether measured at baseline, i.e.
View Article and Find Full Text PDFDespite numerous attempts to discover genetic variants associated with elite athletic performance, an individual's trainability and injury predisposition, there has been limited progress to date. Past reliance on candidate gene studies focusing predominantly on genotyping a limited number of genetic variants in small, often heterogeneous cohorts has not generated results of practical significance. Hypothesis-free genome-wide approaches will in the future provide more comprehensive coverage and in-depth understanding of the biology underlying sports-related traits and related genetic mechanisms.
View Article and Find Full Text PDFDespite numerous attempts to discover genetic variants associated with elite athletic performance, injury predisposition, and elite/world-class athletic status, there has been limited progress to date. Past reliance on candidate gene studies predominantly focusing on genotyping a limited number of single nucleotide polymorphisms or the insertion/deletion variants in small, often heterogeneous cohorts (i.e.
View Article and Find Full Text PDFDNA methylation is modifiable by acute and chronic exercise. DNA methyltransferases (DNMT) catalyze this process; however, there is a lack of literature concerning the specific mechanisms by which exercise-induced modifications occur. Interleukin 6 (IL-6) stimulation of various cell lines has been shown to augment DNMT expression and nuclear translocation, which suggests a possible pathway by which exercise is able to elicit changes in epigenetic enzymes.
View Article and Find Full Text PDFAim: MicroRNAs (miRNAs) are stable in the circulation and are likely to function in inter-organ communication during a variety of metabolic responses that involve changes in gene expression, including exercise training. However, it is unknown whether differences in circulating-miRNA (c-miRNA) levels are characteristic of training modality.
Methods: We investigated whether levels of candidate c-miRNAs differ between elite male athletes of two different training modalities (n = 10 per group)--endurance (END) and strength (STR)--and between these groups and untrained controls (CON; n = 10).
Alpha-actinin-3 (ACTN3) is an integral part of the Z line of the sarcomere. The ACTN3 R577X (rs1815739) polymorphism determines the presence or absence of functional ACTN3, which may influence the extent of exercise-induced muscle damage. This study aimed to compare the impact of, and recovery from, muscle-damaging eccentric exercise on subjects with or without functional ACTN3.
View Article and Find Full Text PDFThe ACTN3 R577X (rs1815739) genotype has been associated with athletic status and muscle phenotypes, although not consistently. Our objective was to conduct a meta-analysis of the published literature on athletic status and investigate its associations with physical capability in several new population-based studies. Relevant data were extracted from studies in the literature, comparing genotype frequencies between controls and sprint/power and endurance athletes.
View Article and Find Full Text PDFA recent study investigating the molecular mechanisms of seed pod shattering has shown that the basic helix-loop-helix (bHLH) proteins INDEHISCENT and ALCATRAZ appear to regulate fruit patterning through gibberellic acid (GA)-DELLA signalling, revealing a central role for bHLH family members in GA response specificity.
View Article and Find Full Text PDFBackground: South Asians are more insulin resistant than Europeans, which cannot be fully explained by differences in adiposity. We investigated whether differences in oxidative capacity and capacity for fatty acid utilisation in South Asians might contribute, using a range of whole-body and skeletal muscle measures.
Methodology/principal Findings: Twenty men of South Asian ethnic origin and 20 age and BMI-matched men of white European descent underwent exercise and metabolic testing and provided a muscle biopsy to determine expression of oxidative and lipid metabolism genes and of insulin signalling proteins.
Studies of the fat mass and obesity-associated (FTO) gene provide compelling evidence of genetic variation in the general population that influences fat levels and obesity risk. Studies of the interaction between genetic and environmental factors such as physical activity (PA) will promote the understanding of how lifestyle can modulate genetic contributions to obesity. In this study, we investigated the effect of FTO genotype, and interactions with PA or energy intake, in young children and adolescents.
View Article and Find Full Text PDFDaughters of diabetes patients have lower insulin sensitivity than women with no diabetes family history, but increase insulin sensitivity to a greater extent with exercise training. This study aimed to determine whether differences in circulating concentrations of adiponectin and leptin, and adipose tissue expression of their genes and receptors played a role. Women offspring of patients with type 2 diabetes mellitus (n = 34; age, 35.
View Article and Find Full Text PDFThe genetically programmed courtship song of male Drosophila melanogaster has a rhythmic repetitive structure of sound pulses that is a critical component of mate recognition. This study investigates the neuronal basis of courtship song production by using the GAL4 enhancer trap paradigm to drive the expression of UASG-tetanus toxin (TNT) and UASG-transformer (tra) in subsets of cells. Of the 727 enhancer trap lines screened for courtship song defects in this way, 38 produced a phenotype, and these were used to drive the expression of Green Fluorescent Protein (GFP), thereby implicating the corresponding neuronal structures.
View Article and Find Full Text PDFThe aim of the present study was to investigate the interaction between the angiotensin-converting enzyme 1 (ACE) I/D polymorphism and energy and macronutrient intakes on adiposity-related phenotypes among toddlers and preschoolers. A representative sample of 2374 Greek children aged 1 to 5 years old was examined (Growth, Exercise and Nutrition Epidemiological Study in preSchoolers (GENESIS)). Dietary and anthropometric (i.
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