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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

The effect of the glycemic index on endurance performance

Vogel, Etresia. January 2007 (has links)
Thesis (M.A.(MHS))-University of Pretoria, 1999. / Summary in English and Afrikaans.
42

A descriptive study examining motivation, goal orientations, coaching, and training habits of women ultrarunners

Krouse, Rhonna Zena. January 2009 (has links)
Thesis (M.S.)--Boise State University, 2009. / Title from t.p. of PDF file (viewed June 7, 2010). Includes abstract. Includes bibliographical references (leaves 51-54).
43

Endurance Sports for Development and Peace: Leukemia and Lymphoma Society's Team in Training

January 2012 (has links)
abstract: This thesis explores the relationship between sports and human rights based on United Nations reports and literature within the growing Sport for Development and Peace (SDP) sector. Recognizing the benefits of sport (including physical activity and play), SDP posits sport as an effective tool for achieving humanitarian, development, and peace objectives. Inspired by the Leukemia and Lymphoma Society's (LLS) Team in Training (TNT) sports charity training model, which provides participants valuable coaching in exchange for charity fundraising, this research looked at the contribution of TNT and endurance sports to SDP for individual and social change. Interviews were conducted with TNT staff and team members (who are recent or current participants of the program) in order to find out specific reasons about why people join the program and to identify the benefits of combining endurance training with charity fundraising and what impacts this had on personal life goals and challenges. Using thematic analysis to identify key themes from the interview data, the study acknowledged the program's successes in developing endurance athletes and raising money for LLS research and services but also found an additional dimension to the merit of the program. The accomplishment of completing four months of training culminating in the completion of an endurance event with the support of team mates and coaches provides a life changing experience for participants. The study concludes that positive impacts of the TNT program can be applied to other organizations, causes and social issues. In particular it showed how endurance sport not only has physiological benefits but can be used as a method of healing and reconciliation, can aid in advocacy and awareness, and promote individual development. / Dissertation/Thesis / M.A. Social Justice and Human Rights 2012
44

Going the Distance: Romantic Relationship Satisfaction and Quality among Endurance Sports Participants

January 2014 (has links)
abstract: Romantic relationships are often viewed as an important, meaningful part of a person's life. Most romantic relationships do not last forever. Research regarding romantic relationship satisfaction and quality have thus grown. The purpose of this study was to determine whether individuals who train for endurance events such as running, cycling, or triathlons with their romantic partner have greater relationship satisfaction and quality than do individuals who do not train with their romantic partner. Participants, 54 males and 60 females whose mean age was 33.4, completed a demographic questionnaire, the Quality of Relationships Inventory (QRI), the Perceived Relationship Quality Component (PRQC), the Relationship Assessment Scale (RAS), and the Revised Dyadic Adjustment Scale (RDAS). Of these 114 participants, 52 trained with their romantic partner. A multivariate analysis of variance (MANOVA) revealed that individuals who trained with their romantic partner reported higher relationship satisfaction and quality compared to those that did not train for an endurance event with their romantic partner. There were no statistically significant differences in relationship satisfaction or relationship quality between men and women or between married individuals and dating individuals. These findings suggest that couples may benefit from engaging in shared activities. / Dissertation/Thesis / Masters Thesis Counseling 2014
45

Time course of performance changes and fatigue markers during training for the ironman triathlon

Joiner, Alexander Jason January 2010 (has links)
Suboptimal preparation for the Ironman triathlon can have detrimental effects on mental and physical condition. The purpose of this longitudinal investigation was to examine the relationship between a number of performance changes and fatigue markers during training for an Ironman as well as immediately after the event, in an attempt to better understand the effects of ultraendurance training. Eighteen athletes training for the Ironman; South Africa, 2009 were recruited for the study. Over the 6 month data collection period body mass, training load (TRIMP and Session x RPE methods), physiological responses (waking heart rate, postural dizziness, sleep ratings), changes in psychological state (profile of mood states - POMS), reported immunological responses (symptoms of illness), biochemical changes (salivary cortisol and alpha amylase) and performance (8 km submaximal running time trial (TT) and race day performance) were measured. These responses were compared to a control sample (n=15). Results show a significant increase (p<0.05) in training load (3899.4 ± 2517.8) four weeks prior to the event. Fatigue scores significantly increased (p<0.05) concurrently with this significant increase (p<0.05) in training. TT performance did not significantly (p<0.05) alter during the time course of training. It was however strongly correlated to training load (R2=0.85) and modestly related to race performance (R2=0.65). The signs and symptoms of upper respiratory tract infections (URTI) were prevalent during the training period, decreasing during the taper and race period. Large standard deviations were found within the majority of the responses. During the final two weeks of preparation, tension scores were significantly increased (p<0.05) while training load significantly decreased (p<0.05) during the final week of preparation. Cortisol increased significantly (p<0.05) immediately post race (0.507±0.15<g.DL-1) and 1.5 hours later (0.796±0.23<g.DL-1). Overall the results indicate that the POMS questionnaire was a sensitive marker of fatigue and stress associated with ultraendurance training, and that the event itself placed a great deal of stress on the athletes which was illustrated by the post event measures.
46

Muscular Differences Between Female Power and Endurance Athletes

Akers, Allen (Roy Allen) 08 1900 (has links)
The purpose of this study was to compare the torque generating capabilities and fatigue responses of female power athletes, female endurance athletes, and age-matched female non-athletic controls.
47

The Effects of Attentional Focus on Performance, Perceived Exertion, Affect, and Kinematics in Recreational Runners

Verhoff, Dave 17 August 2022 (has links)
No description available.
48

The effect of the glycemic index on endurance performance

Vogel, Etresia 03 January 2007 (has links)
There exist a wide variety of metabolic responses to different types of carbohydrates and their influence on metabolism during endurance training. Recent studies revealed that the physiological responses to food are far more complex than was previously appreciated. The rapid release of insulin and the decline in blood sugar levels during the first stages of endurance training are linked to the Glycemic Index of foods. Researchers cannot still make use of the old distinction between starchy and sugary food or simple and complex carbohydrates. These distinctions are based on the chemical analysis of the food, which does not totally reflect the effects of these foods on the body. The Glycemic Index is a more reliable guideline to apply in nutritional management for endurance athletes. The major object of the study was to indicate the importance of utilizing the Glycemic Index (GI) as part of the nutritional preparation for endurance events. The study investigated the advantages of ingesting a Low Glycemic Index meal prior to exercise and compared it with the ingestion of a High Glycemic Index meal. A pretest-posttest design was used. Twelve healthy, male and female cyclists participated in the study. Subjects were selected according to their level of training. The total test period consisted of 14 days, which included two different dietary interventions of 7 days each. Diet -and training analysis were done on the subjects prior to the commencement of the study. Each subject completed three exercise trials. The first exercise trial consisted of a V02max test until exhaustion. Two submaximal trials (65 - 70 % of V02max) followed and were preceded by two dietary interventions. The dietary interventions (7 days each) had the same amount of CHO, fat and protein but differed in the Glycemic Index of the pre-exercise meals. The first pre-exercise meal was a High Glycemic Index (HGI) meal. The second pre-exercise meal was a Low Glycemic Index (LGI) meal. The results of the study indicated the advantages of ingesting a Low Glycemic Index meal prior to endurance exercise. The drop in blood glucose levels significantly differed (p<0.05) with an average of 0.68 mmol/L between the two tests after 10 minutes of cycling. It took 20 minutes for the blood sugar level of the first testto reach the same level of the blood sugar level of the second test. After the ingestion of the High Glycemic Index meal in Test 1, the blood lactate levels were significantly higher (p<0.05) during the first 15 minutes. The total distance covered by the subjects was 22.86 km after the first dietary intervention (High glycemic Index food) and 27.43 km after the second dietary intervention (Low glycemic Index food) although it is not statistically significant due to the small sample size. The difference in the distance covered of the two tests is 4.57 km in a period of 50 minutes. Subjects indicated that they experienced more physical strain (higher RPE values) in Test 1 (High Glycemic Index food) than in Test 2 (Low Glycemic Index food) (p<0.05). The study results support the fact that Low glycemic index food may confer an advantage when eaten prior to prolonged strenuous exercise by providing a slow¬releasing source of glucose to the blood without causing extensive hypoglycemia. Proper preparation and the correct choice of the pre-exercise meal can exclude the occurrence of sudden drops in the blood sugar levels. The Glycemic Index can also be successfully applied during and after events to improve performance. / Dissertation (MA (MHS))--University of Pretoria, 2007. / Arts, Languages and Human Movement Studies Education / unrestricted
49

Inflammation, immune suppression, and iron status in endurance athletes and the effects of antioxidant supplementation

Hopkins, Dawn Marie Weseli 19 February 2003 (has links)
During extreme exercise, athletes experience increased inflammation that is similar to the acute phase response. Endurance athletes, distance runners in particular, are also more susceptible to compromised iron stores. This study evaluated inflammation, immune function and iron status in athletes completing a 50K ultramarathon. Twenty-two well-trained distance runners, 11 males and 11 females, were randomized in a double blind manner into--1) those who consumed 300 mg vitamin E and 1000 mg vitamin C (500 mg twice daily) or 2) placebos--for six weeks before and one week following a 50K ultramarathon race. Blood samples were obtained on 13 separate occasions throughout the study: before supplementation, during supplementation, the day before the race, pre-race, mid-race, immediately post-race, 2 hours following the race, and daily for six days following the race. Plasma levels of ascorbic acid and ��-tocopherol were measured by HPLC with electrochemical detection. Inflammatory cytokines, interleukin-6 (IL-6), tumor necrosis factor-�� (TNF-��), and interleukin-1�� (IL-1��) were measured using standard clinical assays. Each subject recorded immune function in an activity log and incidence of illness was tabulated as number of days ill. Ferritin was measured by enzyme immunoassay. Hemoglobin, hematocrit, and total-iron binding capacity (TIBC) and serum total iron were analyzed by standard procedures. Plasma concentrations of ascorbic acid and ��-tocopherol increased significantly in supplemented subjects (p<0.0001). Although the ultramarathon race elicited an inflammatory response, antioxidant supplementation did not alter the responses of IL-6 and TNF-��, which both increased from pre-race to mid-race, post- and post-2 h (Scheffe post-hoc analysis, p<0.0001) and returned to pre-race concentrations by 1 day after the race. Male supplemented subjects had lower IL-1�� concentrations compared to females consuming the supplement or to males consuming the placebo (ANCOVA, gender/time/treatment interaction; p<0.01) at mid-race (p<0.05 females, p<0.005 males), post 1 and 2 days (all p<0.002). Males had significantly higher ferritin levels than the female subjects (ANOVA, p<0.0001); supplementation resulted in lower ferritin concentrations at post-5 days (p<0.02, ANCOVA treatment time interaction, p<0.005). Supplementation did not reduce the days illness among those consuming antioxidants compared to those consuming the placebos. Ferritin not only increases during inflammation, it also is a measure of iron stores. Females had significantly lower levels of iron than the male subjects for each of the iron parameters measured (hemoglobin and hematocrit both p<0.0001, ferritin p<0.001, TIBC p<0.02) excluding serum total iron. The ferritin concentrations measured in the women were indicative of depleted iron stores (<12 ��g/l), and antioxidant supplementation increased hematocrit levels in the female subjects (p<0.05). This investigation indicates that female distance runners need to be aware of an increased susceptibility to iron depletion compared to their male counterparts. Antioxidant supplementation improved hematocrit levels (p<0.05) among female runners and may improve iron status among females with depleted stores. Although other investigations have suggested that antioxidant vitamins decrease exercise induced inflammation, no profound benefit of supplementation was found in this investigation though a response similar to the acute phase response was elicited by the ultramarathon race. Improvements in IL-i and ferritin in response to antioxidant supplementation may indicate that the supplementation was beneficial, but more research is needed to draw definitive conclusions. / Graduation date: 2003
50

Training intensity distribution, physiological adaptation and immune function in endurance athletes

Neal, Craig M. January 2011 (has links)
Exercise intensity and its distribution is probably the most important and most heavily debated variable of endurance training. Training induces adaptation but also induces stress responses. Controlling the training-intensity distribution may provide a mechanism for balancing these two effects. It has been reported that elite endurance athletes train with a high volume and load, relative to the sport. These athletes spend the vast majority (>80%) of training time at relatively low intensities (lower than the lactate threshold, zone one), and therefore <20% of training time above the lactate threshold (zones two and three). Experimental studies support the beneficial effects of a high training volume in zone one, and show detrimental effects of replacing zone one training with training in zone two. This is likely due to enhanced recovery from training in zone one compared with training in zone two. The acute recovery following training sessions in zones two and three has been reported to not be different, but the recovery following training in zone one has been reported to be faster. Improvements in physiological adaptation and endurance performance have been reported to be greater following training programmes with higher exercise intensities. Therefore, it has been suggested that a polarised training model, which includes ~80% of training in zone one with ~20% of training in zone three is more beneficial than a threshold training model, with the majority of training in zone two. However, research into an optimal training-intensity distribution is limited. Therefore, the aims of this thesis were to assess the effectiveness of training-intensity distribution on the improvements in physiological adaptation, endurance performance and assess if manipulating training-intensity distribution had an effect on immune function. Study one revealed that the lactate threshold, the lactate turnpoint and maximal performance measures in swimming, cycling and running, assessed using the methods outlined in the study, are reproducible in trained endurance athletes. These tests can therefore be used by trained endurance athletes as part of a physiological testing programme to assess not only endurance performance, but also to demarcate training intensity zones for exercise intensity prescription and monitor moderate to large adaptations to training. Practitioners should take care when deciding on the duration between tests to test for adaptations from training, as adaptations need to be greater than these detected test-retest variations to be considered physiologically meaningful. To the best of the author’s knowledge, study two was the first study to have assessed training-intensity distribution in a group of multisport athletes. Training was monitored over a 6-month period, and testing took place every two months to assess the effect of the training on physiological adaptation. Although speculative due to the number of variables involved, the results suggest that a greater proportion of training time spent in zone one and a lower proportion of training time spent in zone two is beneficial to physiological adaptation. However, given the number of variables associated with assessing the training-intensity distribution in multisport athletes, it is not easy to draw conclusions as to the effectiveness of the training in the different disciplines on the key measures of adaptation in the different disciplines. Study two highlighted the need for future research to focus on experimental manipulation of training-intensity distribution and thus improve our understanding of its impact on the training-induced adaptations in endurance athletes. Study three manipulated the training-intensity distribution in trained endurance athletes in just one discipline, to reduce the number of variables involved. A polarised training model was compared to a threshold training model on the effectiveness to improve physiological adaptation and endurance performance. Results revealed that a polarised training model is recommended for trained cyclists wishing to maximally improve performance and physiological adaptation over a short-term (six week) training period. The first part of study four assessed the effect of a polarised and a threshold training model on immune function markers in trained cyclists. Both endurance training programmes had similar volume, and were sufficient to induce improvements in performance and physiological adaptation. However, despite likely differences in recovery, both training programmes had no effect on the proportion of low or high differentiated or senescent CD8+ or CD4+ T-cells in blood. Therefore, training adaptation was achieved at no cost to this particular aspect of immune function. From these results and evidence from previous studies, it seems likely that athletes need to be overreached to induce any change in immune function following a period of intensified training. The second part of study four assessed the impact of an ironman triathlon race on Epstein-Barr virus (EBV) and Varicella-Zoster virus (VZV) antibody titres and the frequency of low and high differentiated and senescent blood T-cells in trained endurance athletes. Previous work has revealed that an ironman triathlon race increases the proportion of senescent CD4+ T cells and decreases the proportion of naive CD4+ T cells, and thus induces changes the immune space which could leave an individual at a greater risk of infection. This study however, did not find any changes in the proportions of these T cell subsets following an ironman triathlon race. The mean results of this study suggest that there is no relationship between EBV and VZV-specific antibody concentrations and the proportion of senescent, low and highly differientiated T cells. However, on analysis of individual subject data, it seems possible that subjects with a high antibody titre for EBV or VZV 3 wks before a competition might be more at risk of infection post race. A greater subject number would be needed in order to make a more conclusive statement about this relationship. The results of this thesis suggest that future research is required in the area of training-intensity distribution. Firstly, our understanding of the physiological mechanisms responsible for the effectiveness of a polarised training model in trained endurance athletes is limited, and thus studies should attempt to address this issue. Our current knowledge on the mechanisms underlying a blunted T cell response following strenous exercise is also limited. A change in the immune space to a greater proportion of senescent T cells and a lower proportion of naive T cells might contribute to this blunted response. In the current thesis however, the proportions of these T cell markers were unchanged following the training/racing interventions. It is possible that with a higher training load, there could be changes in these markers, and thus this is an exciting area that could have potential implications on athlete health. Finally, testing for antibody titres in endurance athletes is possibly an avenue to detect individuals at the greatest risk of infection if subjected to a large physical and/or mental stress. This could have implications on maintaining athlete health and therefore, allowing athletes to train consistently.

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