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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.
221

Anaerobinės treniruotės ir fizinių ypatybių ryšys su 100 metrų plaukimo varžybų rezultatu / Effect Of Physical Properties And Anaerobic Training On 100 Meters Swimming Results In Competition

Vaitkaitis, Emilis 18 May 2005 (has links)
ABSTRACT Effect Of Physical Properties And Anaerobic Training On 100 Meters Swimming Results In Competition Purpose: The objective was to examine which physical property has the biggest influence on 100 meters swimming result and to find out whether anaerobic training increase swimming performance. Methods: The research was devoted into 3 main stages. The goal of the 1-st stage was to examine connection between FINA points and the results of different physical capacity tests. In this stage of research were examined 20 elite swimmers (males, n=20, age 21 ± 2). In the 2-nd stage of the research were examined 37 elite male swimmers (n =37, age 21.6 ± 2.3). The goal is to investigate connections between FINA points and strength indexes. In the third stage of the research 6 male swimmers (age 20 ±1.8) were assigned to the training group. The specific anaerobic training consisted of approximately 60 % anaerobic intensity of all physical loading, 5 times a week, for 6 weeks. The aim of this stage of research was to find out whether anaerobic training increase swimming performance. Results: There are no significant connections between FINA points and the indexes of physical development, indexes of velocity and endurance. The direct coefficient of correlation was observed in FINA points and strength index (r = 0.86, p <0.05, n = 37). 6 weeks of anaerobic training improved swimming result, in distance of 100 meters, approximately 8 ± 3%, also increased index of strength 12... [to full text]
222

CALF HEMODYNAMICS DURING VENOUS OCCLUSION AND HEAD-UP TILT

Kilfoil, Peter J 01 January 2007 (has links)
The potential role of lower limb blood pooling in reducing venous return to the heart during orthostasis and elevated venous pressure is investigated. This study compares lower limb capacitance, microvascular filtration, and peripheral resistance between a group of highly trained endurance athletes and a group of their sedentary peers. Seven endurance trained males were selected between the ages of 23-33 [(29.1 4.1 yr), mean SD]. The subjects weekly cycling mileage ranged from 80 to 150 miles per week with an average of 125 8.5 miles/week. Nine healthy, age-matched sedentary subjects (25.8 4.8 yr.) were selected for the control group, based upon their reporting they had not participated in repeated lower-body or cardiovascular exercise in the months prior to their study. Results show that both subject groups had similar calf venous capacitances, rates of capillary fluid filtration, and local flow shunting (vascular resistance change) in response to venous thigh occlusion and 70 head-up tilt (HUT). The only significant difference found between groups was the cyclist groups smaller rise in heart rate in response to HUT. The findings of this study suggest that cyclists are not predisposed to orthostatic intolerance due to any changes in lower limb function.
223

Elite sprinters, ice hockey players, orienteers and marathon runners : isokinetic leg muscle performance in relation to muscle structure and training

Johansson, Christer January 1987 (has links)
In male athletes from different sports, isokinetic knee extensor, and in orienteers also plantar flexor peak torque (PT), contractional work (CW) and integrated surface electromyograms (iEMG) were analysed. Single contraction PT, CW and iEMG in sprinters and marathon runners were signi­ficantly correlated to the cross-sectional area (CSA) of m. quadriceps, and to the Type II fibre area of m. vastus lateralis. When correcting PT, CW and iEMG for CSA of m. quadriceps, such correlations were found only for Type IIA fibre area at 180° s~1. Elec- tromyographically, m. vastus lateralis (biopsied muscle) was representative for m. quadriceps. Calculated optimal mean power (CW s~1) and electrical efficacy (CW/iEMG) approximated for sprinters 450° s-1 and for marathon runners 270° s~1, i.e. velocities at or above the upper limit of the dynamometers. In orienteers, plantar flexor PT increased during winter training, but decreased during competitive season. Knee extensor PT increased over the whole year. At 30 and 60° s~1 only knee extensor PT was negatively associated with the running velocity at onset of blood lactate accu­mulation (VOBLA)- Changes in VOBLA during winter period were negatively associated with changes in knee extensor PT at 180° s~1. During competitive season, changes in Vobla were negatively associated with the ratio quality : quantity running. In ice hockey players PT varied non-systematically with training and games. The biopsy specimens of marathon runners showed irregular fibre shapes, an in­creased amount of connective tissue and central fibre nuclei, indicating an early strain disease or functional adaptation to extreme demands. During repetitive contractions in sprinters and marathon runners, fatigue, i.e. slope of decline in CW, was significantly associated with the Type II fibre area of m. vastus lateralis. For knee extensors of sprinters, ice hockey players and orienteers, a steep de­crease in CW/iEMG was observed. In contrast, knee extensors of marathon runners and plantar flexors of orienteers showed an almost unaltered CW/iEMG throughout the test. The knee extensor endurance level (CW/iEMG) was significantly correlated to the maximal oxygen uptake. In orienteers, an increase in endurance level of both tested muscle groups during winter training parallelled an increase in VOBLA and V02obla- In hockey players, fatigue and endurance pattern (CW and CW/iEMG) changed non-systematically with training and games. In conclusion, isokinetic measurements and iEMG reflect the structural properties of the knee extensor muscles in sprinters and marathon runners. The demonstrated characteristics and changes in leg muscle function in different groups of athletes apparently reflect varying demands from different sports activities. / <p>S. 1-31: sammanfattning, s. 33-84: 6 uppsatser</p> / digitalisering@umu
224

The effects of cross-country training on male high school runners

Plank, David M. January 1999 (has links)
The purpose of this study is to determine physiological adaptations in trained male high-school runners before and after high-intensity training associated with a crosscountry season. Testing occurred on five separate occasions at the Human Performance Laboratory. After the first familiarization session, the subjects performed a treadmill graded exercise test in which maximal oxygen consumption and ventilatory threshold was measured. Submaximal oxygen consumption and blood lactate concentration at three running speeds (10, 12, and 14 km'hf 1 at 0% grade) was determined in a second testing session. After the cross-country season (13 weeks) the subjects returned to the laboratory and performed the same graded exercise and submaximal exercise tests. VO2max significantly increased, VT tended to increased, however, not significant. There were no changes in submaximal economy or lactate except for significant decline in blood lactate at 14 km hf' . Although these variables are associated with endurance performance in adults, there is very little information available regarding the effects of endurance training on these variables in the adolescent age group. Knowing the extent of the adaptations will help to optimize the training programs for age group. / School of Physical Education
225

The Effects of Aerobic Exercise on Human Skeletal Muscle Adaptations to Resistance Exercise

Lundberg, Tommy January 2014 (has links)
Aerobic exercise (AE) may interfere with muscle adaptations induced by resistance exercise (RE). Three experimental campaigns were conducted to explore the influence of AE on molecular, functional and muscular adaptations to acute and chronic RE. Twenty-nine men performed unilateral knee extensor RE preceded by AE (AE+RE). The contralateral leg did RE only. First, the influence of acute AE on muscle molecular responses to RE performed 6 h later was studied. Subsequently, this exercise regimen was implemented over 5 weeks training. The relationships between acute and chronic outcomes were examined and molecular responses to acute exercise were assessed in untrained and trained muscle. Finally, acute and chronic responses to AE+RE, interspersed by only 15 min recovery, were investigated.Phosphorylation of mTOR and p70S6K was greater after AE+RE than after RE. In parallel, myostatin was suppressed for a longer time after AE+RE. These results suggest that AE+RE enhance skeletal muscle anabolic environment more than RE alone (Paper I). After 5 weeks training, improvements in muscle strength and power were similar across legs. However, AE+RE prompted a greater increase in muscle size than RE, suggesting that AE potentiates the hypertrophic stimulus to RE training without altering muscle function progress (Paper II). Consistent with changes in whole-muscle size, AE+RE showed greater anabolic molecular responses than RE. As chronic training blunted this effect, it appears that AE offers a synergistic hypertrophic stimulus to RE only during short-term training (Paper III). Although putative regulators of hypertrophy such as p70S6K, myostatin and PGC-1a4 were examined, no molecular marker correlated with changes in muscle size, strength or power induced by training. Hence, this study challenges the concept that single molecular markers are viable predictors of training-induced muscle adaptations (Paper III–IV). When recovery time between exercise bouts was reduced to 15 min, AE+RE still produced a more substantial increase in muscle size than RE. However, progression of concentric strength was blunted. Thus, while restored muscle function between exercise bouts is a prerequisite for achieving maximal gains in strength and power, incomplete recovery appears not to compromise muscle hypertrophy (Paper V).Collectively, the results suggest that outcomes of AE+RE are impacted by chronic training and time allowed for recovery between exercise modes. Yet, the current study offers no support to the view that AE interferes with muscle hypertrophy induced by RE.
226

Exploring the role of experiential learning in the development and performance of elite endurance athletes

Jackson, W. David 31 August 2009 (has links)
The primary purpose of this study was to explore how an athlete learns from experience and how this has impacted their development in becoming capable elite international athletes. Based on the qualitative theory of phenomenology, a purposeful sampling technique was used to identify participants who were experts in the phenomena being studied. In-depth interviews were conducted with four elite level triathletes (3 female; 1 male). A thematic analysis completed for each participant revealed a number of general themes. The four central themes that pervaded across participants included Learning from a New Coaching Approach, Learning from Performance, Learning during Performance, and Seeking out Learning. Different types of learning were evident and although the central themes fit with a number of different theories and models of learning, the best fit was the network model that recognizes multiple ways of learning. The relevance of experiential learning and the role of the athlete as an active learner were also highlighted. Implications for athletes and coaches include athletes being encouraged to explore various learning methods and coaches being challenged to create an environment that optimizes an athlete’s learning opportunities.
227

Politics as Endurance: Hannah Arendt and the Three Deaths of Being

Orr, Steven Ray Shadbolt 29 August 2014 (has links)
This thesis examines Hannah Arendt's vita activa in the context of the contemporary political world that is marked by the inclusion of a variety of beings beyond mere human plurality. Understanding that Arendt's work is in opposition to the isolating tendencies of philosophical and bureaucratic thought, I look to the processes of labor and work as methods by which togetherness and worldliness can be recovered. Beginning with Richard Sennett's The Craftsman and Vanessa Lemm's Nietzsche's Animal Philosophy, I draw out a common thread in projects that consider non-human actors as capable of politicking: endurance. Building upon Arendt's work in The Human Condition and On Violence, I suggest that the vita diutina, the enduring life, and the three deaths of being serve as a useful ways of understanding already ongoing political projects that include non-human beings. / Graduate / 0422 / 0615 / sorr@uvic.ca
228

Effects of endurance training on performance and metabolism during a repeated treadmill sprint in females

Tsampoukos, Antonis January 2003 (has links)
A small number of previous cross-sectional studies have examined the relationship between endurance training status on recovery of performance and metabolites from sprinting. However, no longitudinal studies have been undertaken. In addition, there is a dearth of information on female subjects and on running exercise which prompted the need, in the present thesis, to address the effect of menstrual cycle phase on performance and metabolic responses during a repeated sprint run. Thus, the overall purpose of the present thesis was to examine the effect of short-term endurance training on a repeated sprint in female subjects. A number of methodological studies (for which 25 subjects volunteered) were undertaken as preparation for the main experimental chapters of the thesis (Chapter 3). The first methodological study examined the reliability of performance during a 30-s sprint on the non-motorised treadmill. Performance was reproducible as indicated by the 95% limits of agreement for PPO (5 ± 42 W) and by the ratio limits of agreement for MPO (1.01 */÷1.06) during the 30 s sprint. In the second methodological study it was found that capillary lactate concentrations were significantly higher than venous blood lactate after a 30 s sprint (P < 0.05). The third methodological study revealed that a repeated sprint run caused an additional plasma volume loss when compared with the loss caused by a change in posture alone (12.7 % vs 7.5 % for sprint and posture change, respectively, P < 0.05). Finally, it seems that prolonged freezing (up to 13 months) does not have a detrimental influence on whole blood lactate concentration, but repeated defrosting may result in errors in the determination of blood lactate at high lactate concentrations (methodological study 4). The first mam experiment examined the effects of menstrual cycle phase on performance and metabolic responses during a repeated sprint run (2x30 s, with a 2 min passive recovery) in 8 volunteers (chapter 4). Performance was unaltered during the follicular, mid-cycle and luteal phase of the menstrual cycle as reflected by PPO (461 ± 51 and 395 ± 48, 443 ± 43 and 359 ± 44, 449 ± 52 and 397 ± 48 W, for the first and second sprint, during the follicular, mid-cycle and luteal phase, respectively, P > 0.05) and MPO (302 ± 41 and 252 ± 29, 298 ± 37 and 248 ± 29, 298 ± 39 and 252 ± 35 W, for the first and second sprint, at follicular, mid-cycle and luteal phases, respectively, P > 0.05). Similarly, blood metabolic responses were unaffected by menstrual cycle phase as reflected by the unchanged metabolic profile of blood lactate, plasma' ammonia, blood pH and % changes in plasma volume across menstrual cycle. These results suggest that the hormonal fluctuations of 17-,β-estradiol (estradiol) and progesterone, due to menstrual cycle phase, have no effect on repeated sprint performance and possibly on the metabolic responses as reflected by the blood metabolic responses. The second main experiment examined the effects of short-term endurance training on power output recovery and metabolic responses to a repeated sprint run (2x30 s with a 2 min passive recovery) (chapter 5, n = 16). Six weeks of endurance training resulted in a 3% increase (P < 0.05) in V̇ 0₂ max (from 48.7 ± 4.4 before training to 50.17 ± 5.1 mL.kg⁻¹·min⁻¹ after training) in the training group (n = 8) in comparison with 1.9% decrease (from 50.4 ± 1.3 to 49.4 ± 1.2 mL.kg⁻¹·min⁻¹ post-trial) in the control group (n = 7). In addition, % V̇ 0₂ max @ 4 mmol·L⁻¹ [the relative intensity (% V̇ 0₂ max) corresponding to blood lactate concentration of 4 mmol·L⁻¹] was 3% higher (from 82 to 84%) in the training group as compared with the 1% decrease in the control group (from 81 to 80%) (P < 0.05). These endurance adaptations were accompanied by a 7% improvement in MPO recovery (in the second of two 30 s sprints) in the training group in comparison with 2% increases in the control group after training (P < 0.05). Metabolic responses to sprints were unaltered after training, but there was a tendency for higher pH immediately after sprint 1 in the training group in comparison with the control group (7.12 ± 0.07 vs 7.19 ± 0.06 and 7.09 ± 0.07 vs 7.10 ± 0.06, before and after training, in the training and control group, respectively, P = 0.082). These findings suggest that endurance training can be beneficial in terms of quicker recovery of performance during a repeated sprint run. The third main experiment examined the effects of endurance training on performance recovery and muscle metabolites (chapter 6, n=14). Endurance training resulted in a tendency towards lower blood lactate concentrations during sub-maximal exercise in the training group in comparison with the control group (P = 0.063) whilst time to exhaustion for the incremental V̇ 0₂ max test was 12.7% longer for the training group in comparison with 4.1% decrease in the control group (P = 0.095). These endurance training adaptations were accompanied by a 7% improvement (77 ± 7 to 84 ± 5 W) in MPO recovery in the second of two 30 s sprints in the training group while in the control group MPO recovery improved by just 2% (87 ± 8 to 89 ± 8%) (P < 0.05). In addition, similar increases in the recovery of peak speed (3.4% vs 1%, P < 0.05), and mean speed (5% vs 0.9%, P < 0.05) were also evident in the training in comparison with control group. Endurance training resulted in 5.6% decrease in ATP provision from PCr degradation ≈ 14 s post-sprint 1 (P < 0.05) while glycogen degradation was 10% lower (P = 0.063). The latter alterations, in turn, resulted in a tendency towards less reliance on anaerobic energy resources for energy supply after training in the training group (11%, P = 0.098). These results corroborate the findings of chapter 5, but it is still unclear which physiological mechanisms were instrumental in enhancing recovery of performance. It is possible that a faster initial PCr resynthesis or an improved mechanical efficiency or an increased reliance on aerobic metabolism, independently, all together, or in any combination, could have contributed to these improvements in performance recovery. In conclusion the present thesis has shown that: the non-motorised treadmill is a reliable tool for the examination of sprint running performance in the laboratory; that performance and metabolic responses during a repeated sprint run are unaffected by menstrual cycle phase and; that endurance training enhances the recovery of power in female subjects during a repeated sprint run of 2 x 30 s duration with a 2 min passive recovery. The mechanisms underlying the performance improvement following endurance training are unknown, but it is possible that faster PCr resynthesis during the initial phase of recovery (< 1 min) after the sprint is the dominant factor, while greater reliance on aerobic metabolism and improved mechanical efficiency can not be excluded.
229

Anatomical, biomechanical and physiological loading during human endurance performance at selected limb cadences via triathlon

Landers, Grant Justin January 2002 (has links)
Triathlon has had a rapid evolution from its origins 25 years ago in the United States to becoming a full summer Olympic sport in Sydney 2000. It is a sport that combines the three disciplines of swimming, cycling and running linked together with two transitions. It is this combination of events that gives triathlon its uniqueness in the area of exercise science. As a very young sport, the body of knowledge is somewhat limited, but is steadily growing. The following document aims to shed some new light on a range of aspects within the sport of triathlon and highlight triathlon as a sport in its own right with very specific demands when compared with each of the three individual sub-disciplines
230

Hormonal mechanisms of menstrual disturbances, metabolic disorders and effects of oral contraceptives in female athletes /

Rickenlund, Anette, January 2004 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 5 uppsatser.

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