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Evaluation of the Relationship between Venous Function and Post Exercise Oxygen Consumption Recovery KineticsTisdell, Eric Joseph 16 April 2004 (has links)
Excess post-exercise oxygen consumption (EPOC) has been attributed to metabolic, hemodynamic, neuroendocrine, and pulmonary factors. In one particular study, Barclay (J Appl Physiol 1986;61(3):1084-90) suggested that a lower rate of fatigue and hyperperfusion following a bout of exercise was due to a mechanism other than increased oxygen and substrate delivery. Interestingly, few studies have examined the influence of venous function on EPOC. The purpose of this study was to examine the relationship between measures of vascular function and EPOC. Measures of vascular function and VO2 recovery kinetics were examined in 20 individuals [age=22+2.41 yrs]. Nondominant forearm arterial inflow, venous capacitance and venous outflow were evaluated at rest and after 5 minutes of upper arm occlusion, using strain gauge plethysmography. VO2 recovery kinetics was assessed using gas exchange analysis following a six-minute constant work rate protocol at 60 percent of VO2peak, on a cycle ergometer. The average VO2peak was 33.48+8.22 ml/kg/min (Range: 18.7 to 46.1 ml/kg/min). Recovery half-time (T1/2VO2) and Tao were 17.01+3.51 seconds and 54.45+11.28 seconds, respectively. Resting inflow was 2.77+1.51 ml/100ml/min, reactive hyperemic blood flow was 17.72+3.65 ml/100ml/min, venous capacitance was 2.86+0.72 percent, and venous outflow was 34.19+10.03 ml/100ml/min. Bivariate correlations revealed significant associations between T1/2VO2 and the reactive hyperemic response (r=-0.48, p=0.03) and T1/2VO2 and venous outflow post-occlusion (r=-0.50, p=0.02). In conclusion, these findings suggest an important role of both the arterial and venous circulation on EPOC.
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The Effect of Beta-Carotene, Vitamin E, and Vitamin C Supplementation upon Work Capacity during a Protocol of Arm Curl Exercise Using the Biodex DyanamometerGuillory, Ivan Kenyon 11 June 2004 (has links)
The effect of acute and chronic supplementation upon work capacity in trained and untrained subjects was examined using 10 normal healthy subjects (ages 19-23). The subjects were tested using a double-blind crossover design. During the two supplemental stages subjects ingested either the placebo or antioxidant mixture capsules (beta-carotene, vitamin C, vitamin E). There was a 28 day washout period between the two supplemental stages. Subjects were tested during each stage for an acute effect (one day of supplementation) and chronic effect (twenty-eight days of supplementation). Testing consisted of seven sets of arm curl exercises with a 60-second rest period between each set. Work, during the last three sets of each phase, was recorded and compared for each subject. Hypotheses tested was whether an acute (one day) and chronic (28 days) supplementation protocol would have an effect upon work capacity in untrained as compared to trained subjects. No significant differences were seen after acute or chronic supplementation in either trained or untrained subjects. However, power for the study was too low to make a determination without a high risk of Type II error. Significant subject dropout and work measure variability contributed to the low power.
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Instrument Assisted Soft Tissue Mobilization: Effect on Strength and Range of MotionBurnside, John Frederick 01 July 2004 (has links)
OBJECTIVE: The purpose of this study is to determine strength changes in the knee measured throughout full range of motion following Instrument Assisted Soft Tissue Mobilization.
METHODS: 13 subjects underwent pre-screening for existing soft tissue lesions. Subjects performed multiple angle isometric strength testing at the knee (15°, 45°, 60°, 90°, 115° of knee flexion) prior to beginning a 4-week resistance training protocol. Subjects performed knee extension/flexion exercises (2x15) 3 times a week for 4 weeks. Following the training period, subjects were post tested using the same protocol as used in the pre-test.
DATA ANALYSIS: A paired sample t-test was used to determine the difference in isometric peak torque between the control knee and treatment knee. A (2x5) ANOVA was used to compare each angle of isometric force for both knee flexion and extension in the control knee vs. the treatment knee.
RESULTS: Improvements in strength were significant for knee extension in both legs following the 4-week resistance training protocol. No difference was observed between the two legs at each of the 5 angles examined. No significant change in range of motion was observed.
CONCLUSION: Instrument Assisted Soft Mobilization has no effect on ROM and strength changes for healthy subjects, who have no prior history of knee or thigh injury. Its success is documented for therapeutic purposes, but more research is needed in regards to its use for a healthy population.
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Autonomic Nervous System Modulation of the Heart Following a High Carbohydrate Liquid MealBunol, Calynn Davis 21 September 2005 (has links)
The involvement of the sympathetic nervous system in the pathology of obesity has long been a debate among researchers. Various methods of capturing the resting sympathetic activity as well as the response of the sympathetic activity elicited by the introduction of a meal or a bout of exercise in both lean and obese individuals have been investigated. This study examined the autonomic modulation of the heart following a high carbohydrate liquid meal in various body types. Twenty-five females with body mass indexes [weight (kg)/height<sup>2</sup>(m)] ranging from 19.3-39.5 were grouped according to relative basal energy expenditure adjusted for lean body mass (High relative basal energy expenditure - HIGH rBEE and Low relative basal energy expenditure -LOW rBEE). Each female consumed ENSURE with Fiber at a calorie level equal to forty percent of her basal energy expenditure. Heart rate variability was measured for 15min at rest, immediately following the meal, and hourly for 5hrs postprandial. The LOW rBEE group at baseline as well as postprandial tended to demonstrate an elevated sympathetic activity when compared to the HIGH rBEE group (LOW rBEE - resting LF/HF ratio 2.36 ± 2.3, peak increase two hours pp LF/HF ratio 3.09 ± 2.9; HIGH rBEE - resting LF/HF ratio 1.93 ± 1.7, peak increase fifteen minutes pp LF/HF ratio 1.98 ± 0.9). Meal induced thermogenesis, measured as changes in sympathetic activity, was higher in the LOW rBEE group. In conclusion, this study has shown that in the pre and postabsorptive state, individuals with a LOW rBEE tend to be more hyperadrenergic when compared to HIGH rBEE individuals, which may signify an adverse cardiovascular risk. The evidence supports the assertion that when the SNS response to a meal in various body types is being investigated, a duration of greater than 5hrs post prandial is necessary.
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Students' Construction of the Body in Physical EducationAzzarito, Laura 12 August 2004 (has links)
Recently, physical education researchers have been concerned about the results of national studies reporting young people's low level of participation in physical activity and health problems associated with inactivity. In general girls are less active than boys, and youth from low socioeconomic classes are less active and are more likely be unhealthy than middle or upper class youth. Blacks have the highest risks of health problems and the highest levels of physical inactivity. Among a number of recommendations included in Healthy People 2010, physical education has been identified as a fundamental site for addressing today's challenges.
According to physical education researchers, one way to address these issues is to continue investigations that examine the body from a socially constructed perspective and explore how social constructions of the body relate to individuals' participation in physical activity. From this theoretical view, racialized and gendered ideologies about the body may encourage or constrain individuals' participation in physical activity. Feminist post-structuralist and post-modernist theories have been utilized to further this research line.
The purpose of this dissertation was to explore how high school students constructed meanings about the body and how these meanings related to their participation in their physical education classes. Quantitative and qualitative methodologies were employed. The quantitative method entailed the administration of a survey to assess the importance of Bodily Meanings and Discursive Constructs to 529 high school students in three public schools in the southeastern area of the United States. An ethnographic design was employed in four 9th grade physical education classes in two public high schools. This qualitative phase included an observational period of the classes and formal interviews with 28 high school students and three physical education teachers. Findings in this study provide evidence of gender and racial differences in high school students' construction of meanings about the body and demonstrate these gender and racial differences were influential in students' participation in physical education classes. Suggestions are provided for reconceptualizing the physical education curriculum by destabilizing the gendered and racialized body and degendering and deracializing physical education practices.
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Effects of Aerobic and Anaerobic Training Protocols on 4000m Track Cycling Time TrialCheramie, William Mathieu 12 November 2004 (has links)
The aim of this study was to determine whether performance in a 4000m individual pursuit could be significantly influenced by training protocols that are solely based in either aerobic/distance training, or anaerobic/sprint training. Faina et al., (1989) and Neuman et al. (1992) have found, using professional track cyclist that there appears to be a split in energy pathways used to perform the event. Their results indicate that 20% of the workload is achieved via anaerobic metabolism and the remaining 80% are achieved through aerobic metabolism.
Group #1, followed a training protocol modeled after repeated, short duration, (<1:30.00s/1000m), high intensity sprinting. This particular training protocol may serve to utilize a greater proportion of its allotted time by generating beneficial metabolic adaptations that may possibly improve the subjects performance in the 4000m individual pursuit.
Group #2, trained primarily through aerobic means, followed the "more traditional" training method for such an event. This protocol consisted of cycling intervals of distances proportionally longer (>4000m) than that of the actual performance measure. A reasonable assumption could be made, that more could be achieved by improving that area which has an 80% influence over an individual's performance in a single event than that which only accounts for 20%.
Through metabolic and performance testing, the effectiveness of the 4-week training protocols were evaluated via specific values of interest (4000m performance, oxygen consumption, anaerobic threshold, power output and oxygen deficit). Results indicated improved 4000m performance for both groups, though no statistically significant difference between them.
Each training protocol attained their results through adaptations in various metabolic pathways. Though statistically the findings were unable to determine a more successful program, Group #1 yielded a 1.75% advantage over Group #2 in 4000m performance, post training.
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Oxygen Uptake Efficiency Slope and Functional Physical Performance in Elderly AdultsFuller, Scott Eric 26 January 2005 (has links)
Background: The Oxygen Uptake Efficiency Slope (OUES) attained during submaximal treadmill exercise is a reliable index of cardiorespiratory capacity in older adults. This investigation compares OUES values derived during treadmill walking and performance of the Continuous Scale Physical Function Performance test (CS-PFP). Method: A Cosmed portable metabolic cart was used to collect breath gases in 36 older adults (age: 81.8 +/- 7.8 years). Twenty-one subjects performed both the incremental treadmill test and the CS-PFP while an additional 15 subjects performed the CS-PFP, only. Results: The regression of log Ventilation vs. VO<sub>2</sub> reveals similar correlations for the CS-PFP and treadmill derived slopes (Rsquare= 0.78-0.93, and 0.81-0.92, respectively). Moreover, the OUES slopes derived from the CS-PFP and treadmill conditions were highly correlated (ICC = .93). Conclusion: the OUES can be derived during the performance of the CS-PFP, suggesting an economy of testing whereby physical function and cardiorespiratory capacity can be simultaneously assessed.
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The Role of Teachers' Self-Efficacy in Increasing Children's Physical ActivityRoth, James Frederick 04 April 2005 (has links)
It is well documented that elementary school children do not participate in recommended amounts of physical activity, and that elementary physical education programs generally are unable to insure that children engage in appropriate amounts of activity. One solution to this dilemma is to increase childrens activity levels through collaborative efforts such as whole school programs involving the classroom teachers. If this approach is to be successful, it is important to investigate ways that elementary classroom teachers can be actively involved in school level programs that will ultimately increase childrens physical activity levels. Elementary classroom teachers are often responsible for at least a portion of the instructional requirements in physical education, but tend to view this responsibility negatively. Self-efficacy is a powerful theoretical approach for determining and improving a persons participatory behavior and their perseverance in the face of obstacles. This study investigates self-efficacy as a framework to facilitate the involvement of classroom teachers in whole school physical activity programs. The purpose was to investigate how teachers self-efficacy influences their participatory behavior. This was an experimental design involving 148 classroom teachers and their classes from 11 elementary schools (six experimental, six control). Instruments were employed to assess and explain teachers self-efficacy strength and sources, teachers participation, and students participation in a nine-week physical activity intervention. Statistical analyses of the quantitative data confirmed support for (a) self-efficacy theorys predictive aspects of teachers participatory behavior in innovative physical activity programs, (b) a causal relationship between the level of teachers participation and their subsequent self-efficacy, (c) emerging theories of self-efficacys malleability. The themes that emerged from the analyses of the qualitative data reflected the belief that (a) environmental influence on teachers capability beliefs, though still prominent, decreases after actual participation in a program, (b) during participation, teachers shift importance away from more abstract factors to more concrete factors, (c) teachers with enhanced efficacy are more able to negotiate environmental barriers, confirming a central tenet of self-efficacy theory and explaining the findings of the quantitative part of this research project.
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L-Glutamine Supplementation: Effects on Recovery from ExercisePiattoly, Tavis Joseph 17 June 2005 (has links)
Clinical evidence supports the use for exogenous glutamine in the maintenance of muscle
mass and immune system function in critically ill patients. Relatively little research has
examined the benefits of glutamine for athletes engaged in heavy exercise
training, despite a possible link between overtraining and glutamine. PURPOSE: To
examine the influence of Glutamine on time to exhaustion and power after a
prolonged bout of exercise. METHODS: Twelve men (Age: 19 to 30y) involved in cycle
training were asked to participate in the study. All participants performed a
Symptom-Limited Graded Exercise Test (SL-GXT) using the Astrand Cycle protocol. On
a subsequent visit participants performed two Wingate tests on a cycle ergometer to
assess Peak Power, Mean Power, and Fatigue Index. The tests were separated by an
exhaustive bout of exercise at 70% of VO2R. Twenty-four hours later another Wingate
test was performed. Immediately after performing the last Wingate test, subjects were
randomized to: 1. Glutamine plus carbohydrate drink (0.3 grams/kg of body weight/ for 6
days) or 2) Placebo (Carbohydrate drink). After 6 days the Wingate and exhaustive bout
of exercise were repeated in each individual. RESULTS: There were no group
differences in VO2peak (Glu: 44.53+8.75; Pla: 43.83+5.26 ml/kg/min), PP (Glu:
717.71+118.90; Pla: 593.66+117.08), TR (Glu: 38.50+2.26; Pla: 35.50+5.65) and time to
exhaustion (Glu: 46.33+10.80; Pla: 41.90+3.82 ml/kg/min) before supplementation. Both
groups showed a significant drop in PP (-27%, p=0.001), and TR (-22%, p=0.001) after
the exhaustive exercise bout. Incomplete recovery was noted at 24h PP (-17%, p=0.03 vs.
baseline), and TR (-13%, p=0.09 vs baseline). Following supplementation TE improved
by 3.16+0.75min in the Glu group compared to no change in the Pla (p=0.001). Lastly,
the Glu group had similar PP prior to each exhaustive bout of exercise, the PP in the Pla
group was still significantly lower after 6 days. CONCLUSION: Participants in the Glu
group increased time to exhaustion following 6 days of supplementation, and appeared to
recover from exhaustive exercise earlier than the Pla group.
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Hemodynamic and Ocular Responses to Caloric Stimulation and Age-Related DisparitiesdeVeer, Melissa J. 02 September 2005 (has links)
Age-related declines in vestibular function affect balance and coordination in older adults. Of perhaps equal importance, but less understood, are the potential implications of vestibular degeneration on cardiovascular homeostasis. Recent evidence suggests that the semi-circular canals, a section of the vestibular system, may be involved in the vestibulosympathetic reflex (VSR), but the extent to which the aging of the semi-circular canals interferes with cardiovascular homeostasis is unknown. Activation of the intact VSR results in increases in tonometric blood pressure (TBP) and heart rate (HR) as well as decreases in cardiac output (Q) and pre-ejection period (PEP). The purpose of this investigation was to observe reflexive changes in the VSR and cardiovascular function during activation of the horizontal semi-circular canals using bithermal binaural caloric irrigation in young (n =11; 18-39), middle-aged (n = 7; 40-64), and old (n = 9; 65+) adults and to describe age-related changes in cardiac dynamics in order to identify a possible indicator of disease and/or disease risk. 3x2 repeated measures ANOVAs revealed significant increases in slow-phase velocity for all subjects under all conditions, which indicate adequate excitation of the semi-circular canals to stimulate the VSR; TBP increased in the young and middle-aged groups to a greater degree than the old group; RR-intervals tended to decrease in young adults while either decreasing to a much lesser extent or increasing in the middle-aged and old groups. A decrease in RR-intervals indicates an increase in heart rate, and, thus activation of the VSR. Similarly, sympathovagal balance consistently increased in young participants but not in the old adults. These preliminary results cannot confirm an age-related deterioration in semi-circular canal control of cardiovascular function; however, they are sufficient to underscore the importance of the continued investigation of age-related changes in the VSR.
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