888 resultados para 170114 Sport and Exercise Psychology


Relevância:

100.00% 100.00%

Publicador:

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This paper aims to encourage critical reflection on what are key and pressing social and political issues surrounding the Paralympics Games. The focus of the paper is personal narratives of six current elite Paralympic athletes who have participated in at least one Paralympic Games. In response to critical stimuli presented in the form of five ‘unfinished stories’, the self-reflexive, personal, compelling narrative reflections of these individuals were (re)presented for each of the stories as a composite narrative. The stories expose questions over fear, despair, freedom, hope, love, oppression, hatred, hurt, terror, (in)equality, peace, performance and impairment. To really learn from London and reflect for Rio, we need academic work that can understand sport, sporting bodies and physical activity as important ‘sites’ through which social forces, discourses, institutions and processes congregate, congeal and are contested in a manner that contributes to the shaping of human relations, subjectivities, and experiences in particular, contextually contingent ways.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This paper explores the role of digital media and creativity in the processes of learning that occur in groups of urban skateboarders. In particular, it examines how the production and consumption of amateur videos contribute to both skaters’ mastery of the techniques of the sport and their integration into the culture of the sport. The data come from an ethnographic study of skateboarders in Hong Kong, which included in-depth interviews, participant observation and the collection of texts and artifacts like magazines, blog entries and amateur skating videos. Skateboarders use video in a number of ways that significantly impact their learning and integration into their communities. They use it to analyze tricks and techniques, to document the stages of their learning and socialization into the group, to set community standards, to build a sense of belonging with their ‘crews’ and to imagine ‘idealized futures’ for themselves and their communities. Understanding the value and function of such ‘semiotic mediation’ in learning and socialization into sport cultures, I suggest, can contribute to helping physical educators design tasks that integrate training in physical skills with opportunities for students to make meaning around their experiences of sport and physical education.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Oxytocinergic brainstem projections participate in the autonomic control of the circulation. We investigated the effects of hypertension and training on cardiovascular parameters after oxytocin (OT) receptor blockade within the nucleus tractus solitarii (NTS) and NTS OT and OT receptor expression. Male spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats were trained (55% of maximal exercise capacity) or kept sedentary for 3 months and chronically instrumented (NTS and arterial cannulae). Mean arterial blood pressure (MAP) and heart rate (HR) were measured at rest and during an acute bout of exercise after NTS pretreatment with vehicle or OT antagonist (20 pmol of OT antagonist (200 nl of vehicle)-1). Oxytocin and OT receptor were quantified (35S-oligonucleotide probes, in situ hybridization) in other groups of rats. The SHR exhibited high MAP and HR (P < 0.05). Exercise training improved treadmill performance and reduced basal HR (on average -11%) in both groups, but did not change basal MAP. Blockade of NTS OT receptor increased exercise tachycardia only in trained groups, with a larger effect on trained WKY rats (+31 +/- 9 versus +12 +/- 3 beats min-1 in the trained SHR). Hypertension specifically reduced NTS OT receptor mRNA density (-46% versus sedentary WKY rats, P < 0.05); training did not change OT receptor density, but significantly increased OT mRNA expression (+2.5-fold in trained WKY rats and +15% in trained SHR). Concurrent hypertension- and training-induced plastic (peptide/receptor changes) and functional adjustments (HR changes) of oxytocinergic control support both the elevated basal HR in the SHR group and the slowing of the heart rate (rest and exercise) observed in trained WKY rats and SHR.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Aims/hypothesis: Recruitment of the protein c-Cbl to the insulin receptor (IR) and its tyrosine phosphorylation via a pathway that is independent from phosphatidylinositol 3prime-kinase is necessary for insulin-stimulated GLUT4 translocation in 3T3-L1 adipocytes. The activation of this pathway by insulin or exercise has yet to be reported in skeletal muscle. Methods: Lean and obese Zucker rats were randomly assigned to one of three treatment groups: (i) control, (ii) insulin-stimulated or (iii) acute, exhaustive exercise. Hind limb skeletal muscle was removed and the phosphorylation state of IR, Akt and c-Cbl measured.  Results:   Insulin receptor phosphorylation was increased 12-fold after insulin stimulation (p<0.0001) in lean rats and threefold in obese rats. Acute exercise had no effect on IR tyrosine phosphorylation. Similar results were found for serine phosphorylation of Akt. Exercise did not alter c-Cbl tyrosine phosphorylation in skeletal muscle of lean or obese rats. However, in contrast to previous studies in adipocytes, c-Cbl tyrosine phosphorylation was reduced after insulin treatment (p<0.001). Conclusions/interpretation: We also found that c-Cbl associating protein expression is relatively low in skeletal muscle of Zucker rats compared to 3T3-L1 adipocytes and this could account for the reduced c-Cbl tyrosine phosphorylation after insulin treatment. Interestingly, basal levels of c-Cbl tyrosine phosphorylation were higher in skeletal muscle from insulin-resistant Zucker rats (p<0.05), but the physiological relevance is not clear. We conclude that the regulation of c-Cbl phosphorylation in skeletal muscle differs from that previously reported in adipocytes.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Objective To pilot-test a brief written prescription recommending lifestyle changes delivered by general practitioners (GPs) to their patients.

Design The Active Nutrition Script (ANS) included five nutrition messages and personalised exercise advice for a healthy lifestyle and/or the prevention of weight gain. GPs were asked to administer 10 scripts over 4 weeks to 10 adult patients with a body mass index (BMI) of between 23 and 30 kg m− 2. Information recorded on the script consisted of patients' weight, height, waist circumference, gender and date of birth, type and frequency of physical activity prescribed, and the selected nutrition messages. GPs also recorded reasons for administering the script. Interviews recorded GPs views on using the script.

Setting General practices located across greater Melbourne.

Subjects and results
Nineteen GPs (63% female) provided a median of nine scripts over 4 weeks. Scripts were administered to 145 patients (mean age: 54 ± 13.2 years, mean BMI: 31.7 ± 6.3 kg m− 2; 57% female), 52% of whom were classified as obese (BMI >30 kg m− 2). GPs cited ‘weight reduction’ as a reason for writing the script for 78% of patients. All interviewed GPs (90%, n = 17) indicated that the messages were clear and simple to deliver.

Conclusions
GPs found the ANS provided clear nutrition messages that were simple to deliver. However, GPs administered the script to obese patients for weight loss rather than to prevent weight gain among the target group. This has important implications for future health promotion interventions designed for general practice.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Diabetes and obesity are characterised by an impairment in mitochondrial function resulting in a decrease in glucose and fatty acid oxidation, respiration and an increase in intramuscular triglycerides (IMTG's) and insulin resistance. Peroxisome proliferator-activated receptor (PPAR)-ggr coactivator 1agr (PGC-1agr) is a nuclear transcriptional coactivator which regulates several important metabolic processes including, mitochondrial biogenesis, adaptive thermogenesis, respiration, insulin secretion and gluconeogenesis. In addition, PGC-1agr has been shown to increase the percentage of oxidative type I muscle fibres, with the latter responsible for the majority of insulin stimulated glucose uptake. PGC-1agr also co-activates PPAR's agr, bgr/dgr and ggr which are important transcription factors of genes regulating lipid and glucose metabolism. Exercise causes mitochondrial biogenesis, improves skeletal muscle fatty acid oxidation capacity and insulin sensitivity, therefore making it an important intervention for the treatment of insulin resistance. The expression of PGC-1agr mRNA is reduced in diabetic subjects, however, it is rapidly induced in response to interventions which signal alterations in metabolic requirements, such as exercise. Because of the important role of PGC-1agr in the control of energy metabolism and insulin sensitivity, it is seen as a candidate factor in the etiology of type 2 diabetes and a drug target for its therapeutic treatment.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Background: Overuse injury to the patellar tendon (patellar tendinopathy) is a major reason for interrupted training and competition for elite athletes. In both sexes, the prevalence of unilateral and bilateral tendinopathy has been shown to differ. It has been proposed that bilateral pathology may have a different aetiology from unilateral pathology. Investigation of risk factors that may be unique to unilateral and bilateral patellar tendinopathy in female athletes may reveal insights into the aetiology of this condition.
Objectives: To examine whether anthropometry, body composition, or muscle strength distinguished elite female basketball players with unilateral or bilateral patellar tendinopathy.
Methods: Body composition, anthropometry, and muscle strength were compared in elite female basketball players with unilateral (n = 8), bilateral (n = 7), or no (n = 24) patellar tendinopathy. Body composition was analysed using a dual energy x ray absorptiometer. Anthropometric measures were assessed using standard techniques. Knee extensor strength was measured at 180°/s using an isokinetic dynamometer. z scores were calculated for the unilateral and bilateral groups (using the no tendinopathy group as controls). z scores were tested against zero.
Results: The tibia length to stature ratio was approximately 1.3 (1.3) SDs above zero in both the affected and non-affected legs in the unilateral group (p<0.05). The waist to hip ratio was 0.66 (0.78) SD above zero in the unilateral group (p<0.05). In the unilateral group, leg lean to total lean ratio was 0.42 (0.55) SD above zero (p<0.07), the trunk lean to total lean ratio was 0.63 (0.68) SD below zero (p<0.05), and leg fat relative to total fat was 0.47 (0.65) SD below zero (p<0.09). In the unilateral group, the leg with pathology was 0.78 (1.03) SD weaker during eccentric contractions (p<0.07).
Conclusions: Unilateral patellar tendinopathy has identifiable risk factors whereas bilateral patellar tendinopathy may not. This suggests that the aetiology of these conditions may be different. However, interpretation must respect the limitation of small subject numbers.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Objective: Patellar tendinopathy has been reported to be associated with many intrinsic risk factors. Few have been fully investigated. This cross-sectional study examined the anthropometric and physical performance results of elite junior basketball players with normal or abnormal patellar tendons to see if any measures were associated with changes in tendon morphology.

Methods: Agility, leg strength, endurance, and flexibility were measured in 71 male and 64 female players. A blinded radiologist ultrasonographically examined their patellar tendons and athletes were grouped as having normal or abnormal tendons. One-way ANOVA was used to test for differences in anthropometric and physical performance data for athletes whose tendons were normal or abnormal (unilateral or bilateral tendinopathy) on ultrasound.

Results: Results show that females with abnormalities in their tendons had a significantly better vertical jump (50.9±6.8 cm) than those with normal tendons (46.1±5.4 cm) (p = 0.02). This was not found in males. In males, the mean sit and reach in those with normal tendons (13.2±6.7 cm) was greater (p<0.03) than in unilateral tendinopathy (10.3±6.2 cm) or in bilateral tendinopathy (7.8±8.3 cm). In females, those with normal tendons (13.3±4.8 cm) and bilateral tendinopathy (15.8±6.2 cm) were distinctly different from those with unilateral tendinopathy (7.9±6.6 cm).

Conclusion: Flexibility and vertical jump ability are associated with patellar tendinopathy and the findings warrant consideration when managing young, jumping athletes.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Background: This study investigated changes in tendon vascularity in 102 (67 men and 35 women) volleyball players over a 6 month competitive season.

Methods: Athletes were examined with both grey scale ultrasound and standardised colour Doppler settings. Vessel length and pain were measured each month on five separate occasions. Vascular tendons were divided into (i) those that were vascular on all occasions (persistent vascularity) and (ii) those that were vascular on more than two but less than five occasions (intermittent vascularity).

Results: A total of 41 of the 133 abnormal tendons were vascular on two or more occasions. Of these, 16 had persistent vascularity and 25 had intermittent vascularity. There was no significant difference in the prevalence of vascularity between men and women. None of the tendons had a pattern of vascularity over the season that could be clearly interpreted as the onset or resolution of vascularity. Subjects with changes in both tendons were more likely to have persistent vascularity (p = 0.045). Vessels were longer in tendons with persistent vascularity (p<0.000) and pain was significantly greater (p = 0.043) than in tendons with intermittent vascularity. Tendons with intermittent vascularity had similar pain scores on all days, whether or not they had detectable blood flow.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This study used interviews and qualitative analyses to investigate the nature of the messages that preschool children receive from mothers and teachers about their bodies, general appearance, exercise and eating practices. Participants were 10 female teachers and 53 mothers. The behaviours of the 53 children (24 boys, 29 girls) were also observed to determine the nature of their eating and exercise behaviours. The results demonstrated that both mothers and teachers expressed concerns about their own bodies. Mothers also communicated messages to their daughters about losing weight and messages to their sons about increasing their muscles. Both girls and boys were concerned about their appearance, particularly their clothes and hair. Girls also demonstrated some concerns about losing weight, and boys with increasing muscles. Implications of these results are discussed in terms of designing education programs for mothers, teachers and children to prevent the development of body image concerns and disordered eating among children. Copyright © 2006 John Wiley & Sons, Ltd and Eating Disorders Association.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The effectiveness of Cognitive Behavioral Therapy (CBT) for eating disorders has established a link between cognitive processes and unhealthy eating behaviors. However, the relationship between individual differences in unhealthy eating behaviors that are not related to clinical eating disorders, such as overeating and restrained eating, and the processing of food related verbal stimuli remains undetermined. Furthermore, the cognitive processes that promote unhealthy and healthy exercise patterns remain virtually unexplored by previous research. The present study compared individual differences in attitudes and behaviors around eating and exercise to responses to food and exercise-related words using a Lexical Decision Task (LDT). Participants were recruited from Colby (n = 61) and the greater Waterville community (n = 16). The results indicate the following trends in the data: Individuals who scored high in “thin ideal” responded faster to food-related words than individuals with low “thin Ideal” scores did. Regarding the exercise-related data, individuals who engage in more “low intensity exercise” responded faster to exercise-related words than individuals who engage in less “low intensity exercise” did. These findings suggest that cognitive schemata about food and exercise might mediate individual’s eating and exercise patterns.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Objective: Patellar tendon injury, defined by tendon abnormality (TA) on imaging and by pain, is common among volleyball players, but little is known about change in this injury over a volleyball season. Increased activity in the season compared with the off season may result in the development of TA and/or pain. This study investigated the behaviour of TA and pain over a competitive volleyball season.

Methods: Tendon abnormality and pain were measured in 101 volleyball players at the beginning and end of a season. Pain was measured with the single leg decline squat test, which loads the patellar tendon, and TA was detected with ultrasound imaging. Hours of weekly activity were measured and compared during the season and the off season. The proportion of tendons that underwent development and resolution in TA and/or pain over the season was investigated.

Results: Hours of weekly activity was greater during the season than in the off season. Most of the tendons investigated (66.3%) did not undergo a change in TA or pain over the season. Tendon abnormality and/or pain developed in 16.6% of tendons and resolved in 11.2%.

Conclusions: The tendons of volleyball players respond variably to the increased load over the season. Change in TA and pain does not appear to be entirely dependent upon load.