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Biomechanical adjustments over time of an exhaustive run : comparison of compression tights and running shorts / Title on signature form: Biomechanical adjustments over time of an exhustive run : comparision of compression tights and running shortsSchornstein, Barbara J. 24 January 2012 (has links)
Fatigue induces changes to running form; therefore movement is not as effective or efficient. Reducing the amount of fatigue or its effects on form would be ideal to improve performance while running. Compressive clothing has unknown effects on musculature, however it claims to reduce fatigue. The aim of this study was to see the changes in running form while running to exhaustion and to see how compression tights can effect these changes. Eleven runners ran at their current five-kilometer race pace on a treadmill to voluntary exhaustion in a repeated measures design wearing compression tights and regular shorts while their kinematics, kinetics, heart rate and rate of perceived exhaustion were recorded. There was not a significant difference in time to exhaustion. Fatigue general effects were significant from beginning to end in knee and ankle angle at initial contact with the knee becoming less extended and the ankle less dorsiflexed. Vertical ground reaction loading rate and impact peak were significantly different from beginning to mid point and beginning to end across conditions. Heart rate and rate of perceived exertion increased significantly with fatigue as well in both conditions. Condition effects were significant in stride length and rate with a decreased stride length with compression tights and an increased stride rate with compression tights. The hip experienced a decreased range of motion in the compression tights compared to running shorts. These results indicate that there are effects of fatigue on performance and differences between conditions. These differences did not affect the overall outcome of run as measured in time to exhaustion. / School of Physical Education, Sport, and Exercise Science
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The effects of cross-country training on male high school runnersPlank, 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
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Effects of passive and active recovery on the resynthesis of muscle glycogenChoi, DaiHyuk January 1993 (has links)
The purpose of this investigation was to determine the effect of passive and active recovery on the resynthesis of muscle glycogen after high intensity cycle ergometer exercise in untrained subjects. In a cross over design, six college-age males performed three, one min exercise bouts, at 130% V02max with a 4 min rest period between each work bout. Subjects refrained from exercise for two days prior to testing, and consumed a 15% carbohydrate solution (300g sugar in 2000ml of water) the day before each trial to help elevate glycogen concentration. The exercise protocol for each trial was identical, while the recovery following exercise was eitheractive (40-50% VO2max) or passive. The initial muscle glycogen values averaged 144.2 mmol•kg-1 w.w. for the active trial and 158.7 mmol•kg-1 w.w. for the passive trial. Corresponding post-exercise glycogen contents were 97.7 and 106.8 mmol•kg-1 w.w., respectively. These differences were not significant (P>0.05). However, the rate of muscle glycogen resynthesis during passive recovery increased 15 mmol•kg-1 w.w. whereas it decreased 6.27 mmol•kg-1 w.w. following active recovery (P<0.01). Also, the decrease in blood lactate concentration during active recovery was much faster than during passive recovery and significantly different at 10 and 30 min of the recovery period (P<0.01). The major finding of this investigation was that the rate of muscle glycogen resynthesis during passive recovery was significantly greater than that during active recovery. These data suggest that lactate can be used as an endogenous glycogenic precusor in muscle, and that glycogenesis was the prevalent pathway of lactate removal during passive recovery following high intensity cycle ergometer exercise. / Human Performance Laboratory
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Variability of walking and running economy among prepubertal, adolescent and adult femalesGay, Julie A. January 1995 (has links)
Daily variability of walking and naming economy (WE,") was assessed in eight prepubertal (P), eight adolescent (C) and eight adult females (A) on three separate days. Prior to testing all subjects engaged in 15 minutes of treadmill walking and running and performed a graded treadmill exercise test to maximal effort. On 3 additional days WE and RE were measured during five minutes each of walking and running. The order of exercise was randomized and each bout was separated by ten minutes of rest. A one-way analysis of variance (ANOVA) revealed differences (p < 0.05) in height, weight, sum of skinfolds, BSA, VO=Ax (ml-kg' .min 1), HRmAxbetween P vs C, and A. While there were no significant interactions between group and speed, a two-way ANOVA revealed differences between all three groups for WE and RE (p< 0.05). Repeated measures two-way ANOVA revealed significant day-to-day differences in RE but not WE. Coefficients of variation (CV) for economy were significantly greater for walking (4.33) than running (2.33). CV for WE and RE combined were significantly greater in P (4.43) than A (2.42). These results suggest dust daft variability of WE and RE appears to be a function of maturation and growth, with significance being acheived at the extremes of the maturation scale; the prepubescent child and the fully mature adult Furthermore, for research testing purposes, prepubertal children may require greater than two testing sessions, the amount recommended for adults. / Human Performance Laboratory
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Female collegiate windmill pitchers : references to injury incidenceHill, Jennifer L. January 2003 (has links)
There is little research specifically examining fast-pitch softball pitchers. However of the few studies completed, pitchers have been reported to exhibit a high incidence of injury. How and why these pitchers are suffering from injuries has not been elucidated.The purpose of this study was to investigate the injuries occurring to collegiate softball pitchers and factors that may influence these injuries such as demographic, pitching, training, and injury information.A cross-sectional survey of collegiate softball pitchers from Divisions I, II, and III was conducted using InQsit, a web-based survey system. Instructions on how to complete a web-based survey was sent and completed over a two-week period, by 181 Division I, II, and III collegiate softball pitchers. The survey was composed of questions addressing: 1) demographic information, 2) pitching and game data, 3) training program information, and 4) injury reporting.The results showed that demographic information, pitching and game data, and training were not statistically significant (p<0.05) in relation to injury. Among the 131 reported injuries, 36 were acute, 92 chronic, and 3 unspecified. Of the 92 chronic/overuse injuries, 10 were Grade I, 30 Grade II, 39 Grade III, and 13 Grade IV. Of the total injuries, 80 were a direct result from pitching, with 36 relating to the shoulder and 17 to the lower back. Among the injured pitchers, 109 took Non-Steroidal AntiInflammatory Drugs, 140 used modalities, 11 received surgeries, and 95 saw additional specialists. This study revealed that a high percentage (72.8%) of collegiate pitchers are suffering injuries across the nation and more research focused on this area is needed. In addition, coaches need to continue to be informed of ways they can improve the health and training programs of their pitchers. / School of Physical Education
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The effects of graduated exercise at the piano on the pianist's cardiac output, forearm blood flow, heart rate, and blood pressureParr, Sharon M. January 1985 (has links)
The purpose of this study was to determine the effects of graduated exercise at the piano on the pianist's cardiac output, forearm blood flow, heart rate, and blood pressure. Also considered were the effects of piano practice conditioning, general cardiovascular conditioning, and acute cigarette smoking on the aforementioned parameters during and after graduated piano exercise.Fifteen adult pianists participated in the study. The piano exercises consisted of bilateral scales played in eight three-minute stages. Tempo was constant within stages but increased with each new stage. Cardiac output and forearm blood flow were monitored by electrical impedance utilizing a tetrapolar electrode-placement system.FindingsCardiac output, forearm blood flow, heart rate, and systolic blood pressure generally increased proportionally to exercise intensity and returned to basal levels within a five-minute recovery period.ConclusionsStrenuous piano exercise stresses the body in general, not just the active forearm muscles.The stress load placed on the heart by piano playing can be at least as great as that produced by a brisk walk.Piano playing can generate an oxygen debt in the forearm muscles.Conditioning of forearm muscles through regular piano practice results in training effect for piano playing in those muscles.Pianists who participate regularly in quality aerobic exercise programs generally begin and end piano exercise with lower heart rates than those who do not exercise. Frequently, they increase heart rates to a lesser extent during exercise and settle into steady postexercise rates more quickly as well.Both regular piano practice and general cardiovascular conditioning gained through quality aerobic exercise contribute to increased piano-playing endurance.Acute smoking increases cardiac outputs and heart rates of pianists resulting in higher levels of cardiac work during piano exercise.During piano exercise, acutely smoking pianists require greatly increased forearm blood flows to meet muscle needs.
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Age and muscle function : impact of aerobic exerciseDouglass, Matthew D. January 2008 (has links)
The purpose of this investigation was to comprehensively examine the influence of progressive aerobic exercise training on whole muscle size and function in older women (65-80 yr). Three sedentary, healthy, females (66±1 yrs, 167±2 cm, 70±7 kg) performed 12 weeks of supervised progressive cycle training (42 training sessions 3-4 sessions/week up to 80% HRR). Subjects were tested before and after training for maximum aerobic capacity (VO2max), quadriceps cross sectional area (CSA), whole muscle specific tension, concentric 1-RM, maximum voluntary contraction (MVC), and concentric peak power (wafts). On average, the three subjects improved VO2max (34%), quadriceps CSA (10%), MVC (37%), whole muscle specific tension (25%), and concentric peak power (19%). These positive changes indicate that aerobic exercise may positively influence muscle size and function in the elderly. / School of Physical Education, Sport, and Exercise Science
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Single muscle fiber adaptations to resistance training in men and women over 80 YSlivka, Dustin R. January 2006 (has links)
The purpose of this study was to investigate whole muscle and single muscle fiber adaptations in old men (OM) and old women (OW) over 80 years of age in response to progressive resistance training (PRT). Six OM (82±1 y, 74±4 kg, BMI 25±1 kg•m-2) and six OW (85±1 y, 67±3 kg, BMI 27±1 kg•m-2) resistance trained the knee extensors (3 sets, 10 repetitions) at 70% one repetition maximum 3 d•wk-1 for 12 wks. Vastus lateralis muscle biopsies were obtained before and after the PRT program. Isolated muscle fibers were studied in vitro at 15°C for diameter (Dia), peak tension (Po), unloaded shortening velocity (Vo), and absolute peak power (Abs Pwr). With PRT, OM increased whole muscle strength (40±6%, p<0.05), with no change in whole muscle size. OW also increased whole muscle strength (26±6%, p<0.05) without a change in whole muscle size. No differences were observed in any of the single muscle fiber parameters among MHC I or MHC IIa muscle fibers from OM or OW. The novel finding of this study was that despite an increase in whole muscle strength there was no change in whole muscle size, single fiber diameter, or single fiber contractile function. Given that there was no change in muscle size or cellular function with PRT, the improvement in whole muscle strength point to neurological changes. These data suggest that the hypertrophic mechanisms that are typically apparent in humans with PRT are attenuated in individuals over 80 y. / School of Physical Education, Sport, and Exercise Science
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Role of the dopaminergic and cholinergic systems of the rat neostriatum in learning and associative memory functionsViaud, Marc. January 1991 (has links)
The experiments in this thesis investigated the neuropharmacology of memory in the caudate nucleus, using the conditioned emotional response (CER) with visual and olfactory conditioned stimuli (CS). / In experiment 1, post-training, intrastriatal microinjections of both amphetamine and LY 171555, but not SKF 38393: (1) into the posteroventral area improved memory of a visual, but not an olfactory, CER; (2) into the ventrolateral area improved memory of an olfactory, but not a visual, CER. In experiment 2, sulpiride, but not SCH 23390, blocked the memory improving effect of amphetamine. These findings are consistant with the hypothesis that dopamine D2 receptor stimulation mediates the memory enhancement effect of amphetamine in the neostriatum. / In three experiments on a visual CER, pre-training intrastriatal micro-injections of scopolamine impaired acquisition; post-training micro-injections improved consolidation; and pre-testing micro-injections impaired retrieval. These findings are consistant with the hypothesis that striatal muscarinic receptor stimulation mediates some aspects of acquisition and retrieval of sensory-motor memory, and that blockade of these receptors following training has an effect on memory consolidation similar to that of D2-receptor stimulation. / In experiment 6, destruction of the dopaminergic nigrostriatal neurons abolished the memory improving effect of intrastriatal post-training micro-injections of scopolamine and AFDX-384, a specific muscarinic M2 antagonist. These results suggest that the post-training memory improvement produced by muscarinic blockade may be mediated by an M2 receptor, known to be located on dopaminergic nigro-striatal terminals.
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Behavioural investigation of the mammillary region in the ratSziklas, Viviane January 1991 (has links)
The experiments reported in the present dissertation investigated the contribution of the mammillary region to several classes of learning and memory: spatial memory, nonspatial memory, and conditioned aversion learning. It was demonstrated that such lesions impair performance on tasks that require memory for spatial information but that the deficit depends on both the amount of damage within the region as well as the degree of difficulty of the task. A dissociation in the effect of such lesions on performance of comparable spatial and nonspatial memory tasks was shown. In contrast to the severe deficits observed on spatial memory tasks, the acquisition and retention of a complex nonspatial memory task was not impaired after extensive damage to the mammillary region. Such lesions also did not impair performance on two conditioned aversion tasks. These experiments suggest that the mammillary region may be selectively involved in spatial learning and memory. The relevance of these findings to Korsakoff's syndrome is discussed.
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