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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 resistance, endurance, and combination exercise on lipid metabolism and non-traditional cardiovascular disease risk markers in previously untrained men

Martin, Steven Edward 15 May 2009 (has links)
While adhering to an active lifestyle has been associated with a more favorable lipid profile and reduced risk of coronary heart disease (CHD), information regarding the optimal training modality is not well defined. This project examined the acute and chronic effects of endurance (ET), resistance (RT), and combination endurance / resistance (CT) exercise on lipid metabolism and non-traditional CHD risk markers in untrained men. Thirty-one subjects were randomly assigned to participate for 12 weeks in one of three exercise groups: ET, RT, or CT. To measure the effects of acute exercise on lipid metabolism, fasting blood samples were obtained before (baseline) and 24 hours after (24 h) acute exercise (treadmill jogging at 70% V . O2peak, 350 kcals; weight lifting exercise at 70% of 1RM; combination of treadmill jogging and weight lifting at 70% maximal capacity, 350 kcals). Blood variables were adjusted for plasma volume shifts. This acute exercise protocol was completed on two different occasions corresponding to 0 and 12 weeks of training. For acute exercise (pre-training), significant results of a 3 (Group) x 2 (Time) ANOVA, repeated for Time, (p < 0.05) were as follows: TC, HDL-C, HDL2&3-C were lower 24 h after exercise in the RT group. HDL2-C was higher 24 h after exercise in the CT and ET groups. In the ET group, LDL1-C was elevated 24 h after exercise. With all groups combined, LDL3-C and the TC / HDL-C ratio were elevated and LDL2-C decreased 24 h after exercise. For exercise training, significant results of a 3 (Group) x 2 (Training Period) ANOVA, repeated for Training Period, (p < 0.05) were as follows: Body Fat, LDL2-C, and apo A-I were lower after training. Changes in other lipid variables were similar in untrained males performing different types of exercise training. For acute exercise (post-training), significant results of a 3 (Group) x 2 (Time) ANOVA, repeated for Time, (p < 0.05) were as follows: TC, HDL-C, HDL2-C, LDL-C, NONHDL-C, VLDL-C, IDL-C, LDL3-C, LDL density, and LPLa were all higher 24 h after exercise. Post-exercise changes in the dependent variables were similar in trained males performing different types of exercise.
42

Changes in Body Composition and Physical Activity Behavior in a Group of College Freshmen

Swibas, Tracy A 01 August 2007 (has links)
PURPOSE: To compare: 1-the physiological profile of former athletes (Ath) and non-athletes (Non-Ath) upon college entrance, 2-PA levels in these groups, and 3-changes in physiological profile and PA level of former Ath and Non-Ath and females and males over the course of freshman year. Sixty-two college freshmen were tested during the initial weeks of the school year and again during the final weeks of the school year; the sample consisted of 32 former Ath (18 females and 14 males) and 30 Non-Ath (19 females and 11 males). METHODS: Body composition (BC) was assessed using the Bod Pod with a conversion of body density to body fat percentage (%BF) using the Siri equation. PA was assessed using the International Physical Activity Questionnaire (IPAQ), and 7 days of steps were counted using a pedometer. RESULTS: Upon entrance into college, Ath and Non-Ath had similar BC. Daily average number of steps was similar among the groups (Ath: 11212±2729steps; Non-Ath 11191±3735). However, median MET-minutes of weekly total PA (TPA) was higher in Ath (2737 METmin/wk) than Non-Ath (1613 METmin/wk). Over the course of freshmen year, there was a significantly larger drop in TPA for Ath (-1006±2126 MET-min/wk) than Non-Ath (140±2458 MET-min/wk). Overall, Ath had a higher fat free mass (p=0.046). The overall sample experienced unhealthy changes in BC, with a significant average weight gain of 1.81 kg±2.59 kg and a significant decline in daily steps. Males had a significantly larger decline in steps than females (-2374±3720 steps/day vs. -929±2596 steps/day). The overall sample also had a significant decrease in median TPA (2134 MET-min/wk to 1725 MET-min/wk). However there was a wide variation of changes in BC and PA; some had large changes while others had small or none. CONCLUSION: Generally, there were small but unhealthy changes in BC and decreases in PA during freshman year. Former athletes enter college with initially higher activity level when compared to Non-Ath; however this difference disappears by the end of freshmen year. The key is to determine factors that contribute to the large changes in certain individuals and to pinpoint factors that influence college students’ PA behavior.
43

Effect of an energy drink on physical and cognitive performance in trained cyclists

Lassiter, David Gray 03 December 2013 (has links)
This study investigated the effectiveness of an energy drink (ED) in enhancing cycling time-trial performance, and cognitive performance at rest, during moderate-intensity exercise, and after exercise. The protocol was double-blind, randomized, placebo-controlled, two-period, and within-subjects. The treatments were ED containing caffeine and carbohydrate, and a caffeine-free non-caloric flavored placebo beverage (PLA). Exercise performance was measured by time to finish a simulated 35 km time-trial course. Cognitive performance was measured by a Stroop task, a tapping task, a reaction time task, and an executive function task consisting of both tapping and reaction time. The effects of ED on blood markers were also assessed. Race performance was enhanced by an average of 3% when participants had ED compared to PLA without a difference in rating of perceived exertion (RPE). Performance was improved by ED even in participants that arrived to the lab with elevated blood caffeine concentrations. Both before and after the exercise, ED resulted in more taps per second in the tapping task. After receiving ED, plasma insulin spiked, there was a fall in free fatty acids (FFA) and blood glucose remained unchanged. Exercise onset caused a drop in blood glucose when participants consumed ED, though glucose returned to a level that was not different from PLA by 29 km into the race. FFA also increased as the exercise continued, and were not different from PLA by 23 km. ED elevated plasma caffeine levels. Epinephrine was elevated due to ED from 6 km to the end of the race. Norepinephrine was only elevated by ED at 6 km. At rest and throughout exercise ED caused elevated lactate concentrations. When participants consumed ED they sustained a greater VO₂ and heart rate throughout the race. In summary, ED enhanced exercise performance and simple movement time as assessed by the tap test before and after intense exercise. There was enough caffeine in ED to enhance physical performance without causing negative effects on cognitive function. / text
44

Relationship between resistance training and selfreported habitual macronutrienr and energy intake

Shaw, BS, Shaw, I, Brown, GA January 2010 (has links)
Obesity is reaching epidemic proportions and more effective treatments are required to prevent the expansion of this disease. Treatments should focus on creating a negative energy balance either via increasing energy expenditure or by decreasing energy intake, or preferably both. Therefore, the purpose of this study was to investigate whether resistance training can influence feeding behaviour as determined by self-reported habitual macronutrient and energy intake. The effect of eight weeks of resistance training (n = 13) on self-reported macronutrient and energy intake was compared to a non-exercising control group (n = 13) in inactive males using a computer-based software program. Similar to the non-exercising control group, resistance training resulted in no significant (p > 0.05) changes in the habitual intake of daily intake of total kilocalories, carbohydrates, proteins and fats. In conclusion, eight weeks of resistance training is not an effective mode of training to promote an improvement in macronutrient and energy intake and despite studies demonstrating that exercise itself, in the absence of counseling, may affect feeding behaviour, it may be that resistance training as a mode of training may not be an effective mode of exercise to promote overall physical activity in an attempt to modify the patterns of macronutrient and energy intake. As such, negative energy balance would solely be due to the energy expenditure during this mode of exercise.
45

The Effect of Exercise Intensity on Post Exercise Hexose Absorption

Howard, Jason Unknown Date
No description available.
46

The effect of pedometer feedback on physical activity

Mathews, Jamie L. January 2005 (has links)
Inactivity is a risk factor for cardiovascular disease. The use of pedometers for measuring ambulatory physical activity is becoming increasingly popular. One of the potential benefits of wearing a pedometer is acquiring instant feedback. Purpose: The purpose of this study was to determine whether feedback from a pedometer would result in an increase in ambulatory physical activity. Methods: Thirty sedentary adults, six men and twenty-four women, (46 ± 12 years, mean + SD) and BMI, (30.6 + 6.1 kg•m 2, mean + SD) were recruited to wear a New Lifestyles NL-2000 pedometer (capable of storing up to 7 days worth of data) for a total of twelve days. Subjects were divided into two groups. One group received feedback and recorded the number of steps taken four times per day on a log card for the first six days but not the second six days. The other group did not receive feedback the first six days but did the second. The order of whether or not subjects received feedback from the pedometer the first or second six days was randomized.Prior to the study, subjects were not given a recommendation as to how many steps•day' they should accumulate but were given the Surgeon General's recommendation on physical activity. The average number of daily steps for each condition was calculated at the end of each six-day period. Results: No order of effect (whether or not subjects received feedback the first or second week) was evident. Subjects accumulated (mean + SE) 7,409 + 384 steps-day' during the feedback week and 7,041 + 374 steps-day' during the non-feedback week; however, this difference was not statistically significant (p = 0.27). When feedback and non-feedback days were combined and averaged, there were no significant correlations between steps-day' and BMI (r = -0.33) or age (r = -0.33). Conclusions: These findings suggest that feedback from a pedometer resulted in a modest, yet insignificant increase in the number of steps•day-' in a sedentary, adult population when no target step accumulation was assigned. / School of Physical Education, Sport, and Exercise Science
47

Physical activity habits of adults in east central Indiana related to their demographic characteristics

Bone, Stephanie A. January 2006 (has links)
In 1993, it was estimated that poor diet and physical inactivity lead to 300,000 deaths a year in the United States (52). In 1996, the first report on Physical Activity and Health by the Surgeon General was published (80). The major recommendation revealed by the Surgeon General Report was that every U.S. adult should accumulate a moderate amount of physical activity on most, preferably all, days of the week. Strong efforts to communicate the importance of physical activity to the United States population have been somewhat successful. However, trends still fall far short from the goal set forth by Healthy People 2010. Nearly 1 in 4 adults reported no leisure-time physical activity in 2004 (45). The goal is for 20% of the U.S. population to report no leisure-time physical inactivity by the year 2010 (79).It is evident that a large amount of physical activity data and statistics exist. However, physical activity has been traditionally assessed using self-report methods (67). In 1999, the Cooper Institute hosted a conference titled Measurement of Physical Activity. This conference brought leaders in physical activity assessment together with measurement specialists to discuss issues and future direction in physical activity assessment. It was a consensus among researchers that assessing physical activity is a challenging task confounded by various purposes for assessment, populations, and assessment methods. In addition, they found a strong need for the development of assessment devices with sound psychometric properties (89). Self-report instruments have been identified to have numerous reliability and validity limitations.The purpose of this study was to objectively measure the physical activity (pedometer counted steps per day) of adults in East Central Indiana and to assess how these results relate to demographic characteristics and general health indices. Pedometer-measured physical activity (steps) was recorded over a 7 day period and was compared to physical activity data from the IPAQ and to national data obtained via surveys. All subjects also completed a demographic survey.The percentage of subjects who were sedentary was 14.0% which is less than national data demonstrates. Mean steps/day were significantly associated with age, certain income levels, and marital status. An increase in age resulted in a decrease in the mean steps/day. Mean steps/day were also significantly less in the $25,000-$39,999 income level than the >$80,000 group. Those who were either single, divorced, or widowed completed significantly more steps/day than married subjects. Males participated in significantly more vigorous MET•min/week than females. Age was significantly negatively correlated with vigorous MET•min/week, and walking MET•min/week. BMI and income level were negatively correlated with walking MET•min/week. Non-married subjects participated in significantly more vigorous MET•min/week than non-married subjects. The IPAQ classifications were found to agree with the physical activity data from the pedometer measured data. However the relationship (Spearman correlation = 0.325) was relatively weak. / School of Physical Education, Sport, and Exercise Science
48

The effect of repeat exercise on exercise-induced arterial hypoxemia /

Saul, Lloyd. January 2006 (has links)
Exercise-induced hypoxemia [EIAH, arterial PO2 &lt; 90 mmHg and/or alveolar-arterial oxygen partial pressure gradient (A-a DO2) &ge; 25 mmHg] occurs during strenuous exercise in some healthy women. There is conflicting opinion if performing successive bouts of strenuous exercise reduces the severity of EIAH. The aim was to (a) test the hypothesis that the severity of EIAH would be reduced with three successive bouts of strenuous exercise, (b) to determine if repeated bouts of exercise increases hyperventilation thus improving arterial PO2. Seven fit female subjects with EIAH [arterial PO2 or PaO2= 88 +/- 2 mmHg, A-a DO 2 = 25 +/- 3 mmHg and 7 fit female control subjects (PaO2 = 100 +/- 5 mmHg, A-a DO2 = 16 +/- 5 mmHg) performed three bouts of intense exercise on a cycle ergometer at 236 +/- 27 watts [oxygen consumption at end of each set = 48 +/- 6 mL/kg/min, or 96 +/- 5% of maximum] for 5 min each with 10 min of rest between sets. Arterial PO 2 increased [EIAH Delta = +4 +/- 5 mmHg. 95% CI = 0.6 to 7.8; Control Delta = +2 +/- 2 mmHg. 95% CI = 0.4 to 3.6] and arterial PCO 2 or PaCO2 decreased [EIAH Delta = -5 +/- 4 mm Hg, 95% CI = -7.4 to -2.2; Control Delta = -4 +/- 2 mmHg, 95% CI = -5.8 to -2.4] between set 1 and set 3 (P&lt; 0.05). Also, 34% of the variance in the change in PaO2, was explained by the variance in the change of PaCO2 (P &lt; 0.05). In conclusion, repeat exercise improves PaO2, which is related to improved hyperventilation.
49

The Effect of Exercise Intensity on Post Exercise Hexose Absorption

Howard, Jason 06 1900 (has links)
The effects of exercise intensity on post-exercise measures of intestinal permeability and absorption in sedentary and in active young men were examined in this study. Measures were compared bewteen rest, low intensity and high intensity interval exercise interventions. In spite of the exercise interventions being matched for work output, the high intensity interval intervention caused an increase in blood lactate and respiratory exchange ratio during the performance of exercise. No between intervention effect was found in hexose absorption. Active individuals had greater passive transcellular absorption (as measured with mannitol) than sedentary individuals after 2 hours of measurement. Significant differences in hunger measures were found between sedentary and active participants, with active participants recording increased measures of hunger. In conclusion, the hypothesis that that exercise intensity modulates post-exercise hexose absorption was not confirmed. However, measures of intestinal permeability suggest differences in digestive tract function may exist between sedentary and active individuals.
50

Re-evaluation of exercise-induced muscle soreness : an immunohistochemical and ultrastructural study /

Yu, Ji-Guo, January 2003 (has links)
Diss. (sammanfattning) Umeå : Univ., 2003. / Härtill 5 uppsatser.

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