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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

Effects of running on hormonal growth factors

Blostein, Ashley C. January 1993 (has links)
To determine the influence of running on certain blood-born parameters that are involved in bone metabolism, serum levels of calcium, alkaline phosphatase (ALP, a marker of bone formation), growth hormone (hGH), and parathyroid hormone (PTH), were analyzed in 10 male subjects following a 40 min. run at 70% VO2max. Each trial was preceeded by 1 day of inactivity, a 8-12 hr. fast, and drawing of a baseline blood sample by venipuncture. All other blood samples were taken via an indwelling catheter which was inserted in an antecubital vein immediately following the completion of the exercise bout. When the catheter was in place, an "immediate post" sample was drawn. Subsequent samples were taken at 1, 2, 3, 4, 5, 10, 15, 20, 30, 45, and 60 min. after the immediate post sample. Analysis of serum calcium concentrations demonstrated that levels were significantly elevated by 12% following exercise, going from a fasted level of 9.7 ± .53 mg/dl to post-exercise levels of 11.8 ± .73 mg/dl. Serum calcium remained elevated during the first 4 min. following exercise. By 5 min. post-exercise, calcium levels dropped to levels that were significantly lower than the post-exercise sample. However, serum alkaline phosphatase did not change significantly following exercise, as the values remained within normal range throughout the experimental period. Concentrations tended to decrease over time but were not significantly lower than the preor post-exercise levels by the end of the sampling period. Serum concentrations of hGH were more than doubled following a single bout of exercise, going from 4.0 ± 0.98 ng/ml before exercise to 8.8 ± 1.6 ng/ml immediately post-exercise. Following this initial rise, hGH progressively declined and returned to baseline values by 30 min. post-exercise. The concentrations of PTH did not change significantly following exercise. The postexercise sample tended to be higher than baseline values but were not significantly different. The results presented here indicate that an exercise bout 40 min. at 70% V02max results in an elevation of serum calcium and hGH, but does not alter PTH secretion or ALP activity. The data presented in this study indicate that the temporary rise in calcium following exercise is unrelated to PTH. It is hypothesized that the increase in calcium that we observed is attributable to lactate accumulation that would result from an exercise bout of this nature. The buildup of lactic acid and drop in pH causes a dissolution of the crystaline calcium hydroxyapatite compartment of the skeleton, thus causing an increase in ionized calcium. It is not known whether a single bout of exercise can influence hormonal secretion to a sufficient degree to affect bone density, but the hormonal changes demonstrated here could be involved in long-term effects of training. / School of Physical Education
42

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 shorts

Schornstein, 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
43

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
44

Variability of walking and running economy among prepubertal, adolescent and adult females

Gay, 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
45

Endurance training adaptations in adolescent female cross-country runners

Woodruff, Megan E. January 2005 (has links)
This study evaluated the training adaptations in female adolescent cross-country runners over two training seasons. Although the effects of endurance training in this population are understood, the specific adaptations resulting from pre-season and in-season training are not clear. The physiological changes occurring over these two training seasons in 10 female runners (15.7 ± 0.8 yrs, 165.6 ± 5.6 cm, 53.8 ± 6.1 kg) were assessed. Maximal exercise responses were measured during a continuous graded exercise test and submaximal exercise responses were quantified at 7 and 8 mph. Isokinetic muscle strength was assessed at four movement speeds (60-240°/sec) and muscle power was calculated using vertical jump height. Body composition also was assessed. HR at maximal and submaximal exercise declined during pre-season training and then increased during in-season training. Blood lactate [BLa] measurements at 7 and 8 mph decreased following summer training. Whole body bone mineral content (BMC) and bone mineral density, and femoral head BMC increased. In conclusion, it appears that high volume, low intensity training lowers [BLa] with no corresponding change in oxygen utilization in highly trained female adolescents. Running also appears to have a positive impact on bone mass in female adolescents. / School of Physical Education, Sport, and Exercise Science
46

The muscle specific protein synthesis response to acute running exercise utilizing multiple stable isotope tracers

Crane, Justin D. January 2008 (has links)
The purpose of this study was to compare the anabolic response to acute running exercise in two different leg muscles in endurance-trained men using two different stable isotope tracers. 6 male subjects (26±2 yr; V02max 63±2 ml•kg-' •min-') performed a 45 min treadmill run at 77±1 % intensity. Infusions of d3-leucine and d5-phenylalanine were used to measure mixed muscle FSR at rest and 24 hr post-exercise. An additional infusion of 10% amino acid solution was added to the post-exercise infusion to maximize the muscle anabolic response. Muscle biopsies were obtained from the vastus lateralis (VL) and soleus (SOL) at 2 and 6 hr of the infusion for the measurement of isotope incorporation. Additional muscle biopsies were obtained prior to and 4 hr post-exercise for determination of muscle glycogen use. At rest FSR was similar between the VL and SOL using either tracer (p>0.05). At 24 hr post-exercise FSR was elevated in both muscles, independent of the tracer used (p<0.05). Muscle glycogen was decreased to the same extent in both muscles by -31% at 4 hr post-exercise (p<0.05). These data suggest that the VL and SOL muscles are both stimulated similarly during 45 min of level grade running. Additionally, both muscles respond similarly 24 hr post-exercise, independent of the tracer used for the determination of protein synthesis. / School of Physical Education, Sport, and Exercise Science
47

A comparative study of acute responses to running in elite black and white marathon athletes

Bosch, Andrew Norman January 1985 (has links)
Experienced male marathon runners, 9 black and 10 white, with marathon times of 2 hours 45 minutes or faster, acted as subjects for the study, the purpose of which was to determine whether black runners are better suited to marathon running than whites. Body composition was determined by anthropometry. Maximal oxygen uptake (VO₂ max) and other physiological variables were measured during a continuous, speed-incremented treadmill protocol using a computer-aided data acquisition system. Subjects also ran a simulated marathon at 92.5% of the running speed at which the ventilatory threshold (VT) occurred. Physiological, gait and RPE variables were measured at 10 minute intervals during the marathon. Major findings are detailed below:- The VO₂, max averaged 60.4 ∓ 6.5 and 63.2 ∓ 2.9 mI. kg⁻¹.min⁻¹ in the black and white runners respectively and was highly correlated with best marathon race time (r = 0.86 and 0.85 respectively) and VT (r = 0.84 and 0.60 respectively) (p < 0.05). No significant differences existed between the groups in submaximal oxygen uptake (VO₂,) or % VO₂ max utilised at 16 km.hr⁻¹, but the estimated % VO₂ max utilised during a marathon race was higher in the black (89.0 ∓ 5.5%) than the white runners (81. 5 ∓ 3.1%) {p .( 0.05). The % VO₂ max utilised at 16 km.hr⁻¹ (84.8 ∓ 9.1 and 78.6 ∓ 5.8% in the black and white runners respectively) was significantly correlated with the % VO₂, max utilised while racing in the white (81.5 ∓ 3.1%) (r = 0.70) (p < 0.05), but not the black runners (89.0 ∓ 5.5%). The VT occurred at 82.7 ∓ 7.7 and 75.6 :∓ 6.2% VO₂; max in the black and white groups respectively (p < 0.05). Post-marathon blood lactic acid levels were lower in the black (1.30 ∓ 0.26 mmo1.l⁻¹) than the white runners (1.59 ∓ 0.20 mmol.l⁻¹). The respiratory exchange ratio (R) was higher in the blacks than whites when running at 16 km.hr ⁻¹ (1.03 ∓ 0.07 and 0.98 ∓ 0.03 respectively) and during the marathon (p < 0.05). There was no significant difference in pulmonary minute ventilation (Vı) between the groups, but breathing frequency (f) was higher in the black (59 ∓ 12 breaths.min⁻¹) than the white runners (45 ∓ 8 breaths. min⁻¹ ) and tidal volume (V⊤) lower in the black ( 1.33 ∓ 0.16 l.breath⁻¹) than the white runners (1.75 ∓ 0.36 I.breath⁻¹) during submaximal running at 16 km. hr⁻¹ (p < 0.05). The same trend was observed during the marathon run. During the time-course of the marathon f increased and V⊤ decreased In both groups (p < 0.05). Stroke volume decreased and heart rate increased In both groups during the time-course of the marathon (p< 0.05). Cardiac output was therefore maintained. Thermal responses were similar in the two groups. A significant increase in rectal temperature coincided with a decrease in skin temperature and may have been related to an increase in f (r = 0.86 and 0.67 in the blacks and whites respectively), H/R (r = 0.70 and 0.67 respectively) and "local" (leg) RPE (r = 0.84 and 0.82 respectively). It was concluded that black runners were able to run marathon races at a higher % VO₂ more than whites due to the blacks having lower blood lactic acid levels when running at a similar % VO₂ max. Given similar maximal oxygen uptakes, this would enable blacks to run faster. Cardiopulmonary adjustments occur during the time-course of a marathon which maintains Q and Vı
48

The effects of a combined weight training and running program on body composition in college males

Hesslink, Robert L., Jr. 01 January 1983 (has links)
The present study attempted to investigate whether a combined weight and endurance training program can elicit more favorable changes in body composition than either method of training alone. Body composition parameters (absolute fat and fat-free weight) were evaluated using circumference measurements, skinfolds and hydrostatic weighing. Cardiorespiratory fitness was evaluated via a modified Harvard step-test. All tests were administered before and after 10 weeks of training. Exercises were performed 3 days/week for 40 minutes/day. Male volunteers (n=21) were randomly assigned to one of three treatment groups (weight training only, endurance running only, combined weight training and endurance running).
49

The Psychophysiological Effects of a Running Program on Depression, Self-Esteem and Anxiety

Hannaford, Charles P. (Charles Page), 1951- 12 1900 (has links)
The purpose of the present study was to investigate the psychophysiological effects of exercise on measures of cardiovascular fitness, depression, self-esteem, and anxiety. The 1.5 mile run (Cooper, 1972) was used to determine changes in cardiovascular fitness. The Zung Self-Rating Depression Scale was used to measure varying levels of depression. The Rosenberg Self-Esteem Scale was used to measure self-esteem. The Spielberger State-Trait Anxiety Inventory was used to measure state anxiety. An Electromyographic Assay and Digital Skin Temperature were performed on the Experimental and Corrective Therapy Groups in order to measure physiological concomitants of anxiety. A Body Composition Assay was performed in order to measure changes in body composition.
50

Reliability of a Graded Exercise Test During Deep Water Running and Comparison of Peak Metabolic Responses to Treadmill Running

Mercer, John A. (John Andrew) 05 1900 (has links)
Populations that utilize deep water running (DWR) are described in Chapter I. A review of the literature concerning maximal and submaximal responses during DWR, shallow water running and swimming is presented in Chapter II. The protocols to elicit maximal responses during DWR and treadmill running (TMR), subject characteristics, and statistical methods employed are described in Chapter III. The results, presented in Chapter IV, indicate that the DWR protocol is a reliable test for eliciting peak oxygen consumption and heart rate. Furthermore, the metabolic responses during DWR are lower than TMR. Chapter V discusses factors which might limit maximal responses during DWR. Chapter VI contains suggestions for further research. Raw data are presented in Appendix A.

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