272 research outputs found

    Paratriathletes' physiological and thermoregulatory response to training load and competition

    Get PDF
    Paratriathlon is a multi-impairment, endurance sport which made its Paralympic Games debut in 2016. Athletes’ impairments typically include but, are not limited to, spinal cord injury; cerebral palsy, or other neurological disorders; amputations or visual impairments. However, despite athletes displaying impairments that present several considerations for coaches and practitioners, there has been very little research in the sport. Specifically, there is little understanding of how athletes’ impairments may impact their physiological response to acute or chronic changes in training load. Similarly, it is not known how consequences of athletes’ impairments affect thermoregulation and the ability to adapt to the heat. Thus, this thesis aimed to elucidate these unknown areas whilst bridging the knowledge gap to research in able-bodied triathlon. The first two studies of this thesis investigated paratriathletes’ response to changes in training load, longitudinally (Chapter four) and more acutely (Chapter five). [Continues.

    Mucosal immune and physiological responses to exercise in wheelchair athletes

    Get PDF
    Apart from motor and sensory function loss, an injury to the spinal cord can cause sympathetic dysfunction, which has been shown to affect immune responses. In this thesis, data from five experimental studies have been collected to compare physiological and psychophysiological exercise responses between wheelchair athlete subgroups with different disabilities (tetraplegic, paraplegic, and non-spinal cord-injured). In two preparatory studies, physiological exercise responses to exhaustive (Chapter 4) and submaximal exercise (Chapter 5) were investigated in all three disability subgroups. Whilst reliability measures for peak oxygen uptake (VO2peak) were in a range observed previously in able-bodied athletes, the variation in tetraplegic athletes was larger when expressed relative to their VO2peak, questioning the use of this variable to track small changes in aerobic capacity in athletic populations. Submaximal physiological and psychophysiological exercise responses were found to be similar between disability subgroups when expressed as a percentage of VO2peak, justifying the protocol used in the laboratory study on mucosal immune function, which was based on the same percentages of VO2peak for all disability subgroups. The most extensive study of this thesis, detailed in Chapter 6, showed that single laboratory-controlled 60-min exercise sessions increase both salivary secretory immunoglobulin A (sIgA), a marker of mucosal immunity, and α-amylase, a marker of sympathetic activation in all three disability subgroups. However, the impaired sympathetic nervous system in tetraplegic athletes seemed to influence the fine-tuning of their sIgA response when compared with paraplegic and non-spinal cord-injured athletes, resulting in a larger exercise-induced increase of sIgA secretion rate when compared to paraplegic and non-spinal cord-injured athletes. Based on these results, the study detailed in Chapter 7 investigated sIgA responses in tetraplegic athletes during wheelchair rugby court training. Despite their disability, these athletes showed responses thought to be governed by the sympathetic nervous system, such as reductions of saliva flow rate as a result of strenuous exercise. Similarly, the responses observed in Chapter 8 imply a comparable trend of chronic sIgA exercise responses in tetraplegic athletes as found in the able-bodied population, namely a decrease in sIgA secretion rate during periods of heavy training. These are the first studies in wheelchair athlete populations to investigate mucosal immune responses. Interestingly, despite the disruption of their sympathetic nervous system, some responses in tetraplegic athletes are comparable with findings in able-bodied populations. It is possible that due to their highly trained nature, these tetraplegic individuals are able to compensate for their loss of central sympathetic innervation. This may be by way of adapted spinal reflex or parasympathetic nervous system activity, or increased sensitivity of receptors involved in autonomic pathways. Therefore, sympathetic nervous function in tetraplegic athletes may be qualitatively altered, but in parts still be functional

    TFOS Lifestyle: Impact of nutrition on the ocular surface: TFOS Lifestyle Workshop: Nutrition report

    Full text link
    Nutrients, required by human bodies to perform life-sustaining functions, are obtained from the diet. They are broadly classified into macronutrients (carbohydrates, lipids, and proteins), micronutrients (vitamins and minerals) and water. All nutrients serve as a source of energy, provide structural support to the body and/or regulate the chemical processes of the body. Food and drinks also consist of non-nutrients that may be beneficial (e.g., antioxidants) or harmful (e.g., dyes or preservatives added to processed foods) to the body and the ocular surface. There is also a complex interplay between systemic disorders and an individual's nutritional status. Changes in the gut microbiome may lead to alterations at the ocular surface. Poor nutrition may exacerbate select systemic conditions. Similarly, certain systemic conditions may affect the uptake, processing and distribution of nutrients by the body. These disorders may lead to deficiencies in micro- and macro-nutrients that are important in maintaining ocular surface health. Medications used to treat these conditions may also cause ocular surface changes. The prevalence of nutrition-related chronic diseases is climbing worldwide. This report sought to review the evidence supporting the impact of nutrition on the ocular surface, either directly or as a consequence of the chronic diseases that result. To address a key question, a systematic review investigated the effects of intentional food restriction on ocular surface health; of the 25 included studies, most investigated Ramadan fasting (56%), followed by bariatric surgery (16%), anorexia nervosa (16%), but none were judged to be of high quality, with no randomized-controlled trials

    Training, nutrition and exercise immunology: The use of salivary Epstein Barr Virus DNA as a marker of in vivo immunity

    Get PDF
    Aim: The aim of this thesis was to investigate the use of salivary Epstein-Barr virus (EBV) DNA as a marker of in vivo immunity in response to training and nutritional intervention. Methods: Initially, an assay for the detection of EBV DNA in saliva was developed which was subsequently used to detect the concentration of EBV DNA in samples collected in subsequent studies. The potential role of EBV as a predictor of URTI in response to endurance exercise are presented, along with the outcome of nutritional interventions, with chapters investigating the effects of supplementation with carbohydrate, and Chlorella pyrenoidosa. Finally, data from all four of these chapters were consolidated, and the role of salivary EBV DNA as a marker of in vivo immunity investigated. Outcome: The main finding from this thesis is that salivary EBV DNA does not appear to be a useful marker of in vivo immunity based on the present data. EBV concentration was not a predictor of URTI, nor was there a relationship between EBV concentration and SIgA concentration or secretion rate, or the absolute change or percentage change in EBV from pre-post exercise and the absolute and percentage change in SIgA concentration or secretion rate

    Nutraceuticals and Human Health

    Get PDF
    In this Special Issue, we have published papers on the health-promoting effects of nutraceuticals from different sources, and their effects in different pathologies. Extracts from plants have been analyzed, for example, extracts from olive leaves, Mikania micrantha, the devil’s claw, raspberries and others, alongside marine phytoplankton, egg-yolk and marketed dietary supplements. The effects of these extracts and dietary supplements have been studied in diseases associated with obesity, and in diseases where inflammation pathways are involved. The effectiveness of resveratrol and curcumin to support the anticancer activity of cisplatin has also been reported, as well as the ability of devil’s claw root extract to stimulate the CB2 receptors in synoviocytes in osteoarthritis patients. The anti-oxidant effect of marine phytoplankton has been studied on muscle damage, both in humans and in an animal model, and the effects of the metabolite of antocianin were analyzed in a mouse model of amyotrophic lateral sclerosis. Finally, reviews on the use of lactoferrin, ω3 and ω6 and abscisic acid have been reported, in addition to the crosstalk between prostate cancer and microbiota inflammation. Although it is not yet possible to draw definitive conclusions on the use of nutraceuticals, several mechanisms of action for many of them have been further clarified

    Fluid and energy deficits : hydration markers, saliva immunoglobulin A and endurance performance

    Get PDF
    EThOS - Electronic Theses Online ServiceGBUnited Kingdo
    • …
    corecore