This thesis investigated the cost-effectiveness of a 12-month supervised aerobic walking program with or without a behavioural intervention and an educational pamphlet, compared to an unsupervised/self-directed educational pamphlet intervention, among individuals with moderate osteoarthritis (OA) of the knee. Analyses included an economic evaluation to assess the cost effectiveness of the two walking interventions from both the societal and Canadian provincial/territorial health care payer perspectives. A value of information analysis exploring the potential value of future research was also performed. Results revealed that the unsupervised/self-directed intervention was the most cost-effective approach given that it cost the least to implement and participants had higher quality-adjusted life years (QALYs). Walking, either supervised in a community setting, or unsupervised in a setting such as the home, may be a favourable non-pharmacological option for the management of OA of the knee. The thesis concludes with a policy discussion relating to the funding of non-pharmacological therapies.

Increasing evidence supports the use of physical activity for modifying brain activity and overall neurological health (Hillman et al, 2008). Specifically, aerobic exercise appears to improve cognitive efficacy with regards to decisional oddball tasks shown through the P300, whose amplitude and latency is augmented (Magnié et al., 2000). Furthermore, the effects of an acute bout of aerobic exercise on cardiovascular function are well established and are sustained following exercise cessation. Based on these findings, we proposed that (1) an acute bout of exercise may modulate movement-related cortical excitability within motor areas and (2) that transient effects would be sustained as long as heart rate (HR) remained elevated. Subjects (n=23) were placed in a soundproof booth and instructed to perform a self-paced unimanual ballistic wrist extension every 3-6 seconds of the right wrist while holding a moveable handle. The motion involved a brisk contraction followed by relaxation and positional reset, collected continuously for approximately 8 minutes. Electroencephalography was used to measure movement-related cortical activity of the Bereitschaftspotential (BP) time-locked to onset of muscle activity associated with movement. The BP is a slow negative self-paced movement related cortical potential that precedes movement by approximately 1500ms. Current work commonly separates the BP into 3 main components early, late, and re-afferent Potentials. The early BP is representative of motor preparation of supplementary motor area (SMA) activity while the late component is representative of motor execution from primary motor cortex (M1). Early and late components are often distinguished by a a characteristic change in slope; where the early BP is a slow negative rise and the late components a steeper negative deflection beginning approximately 500ms prior to movement onset. Broken down further the late component consists of a portion of negative slope before giving rise to a peak approximately 100ms after movement onset known as the motor potential (MP). Following baseline measures, subjects performed 20 minutes of aerobic exercise at a moderate intensity (70% of age-predicted maximum heart rate) on a recumbent cycle ergometer. After the cessation of exercise, BP measures were recorded at two time points: immediately post-exercise (Post) and following a return to iv baseline HR (Post[Rest]) and two additional measures separated by 15 minutes each (Post[Rest2] and Post[Rest3]) which was, on average, 45 minutes after the cessation of exercise. Electromyography (EMG) was employed over the extensor carpi radialis muscle belly to describe muscle burst activity and onset characteristics. Results determined that Early but not Late BP was influenced by aerobic exercise. This early movement related cortical adaptation is indicative of enhanced processing within supplementary motor area. Moreover, this effect was sustained for up to an hour and 15 minutes following exercise cessation. This data is suggestive that aerobic exercise influences on motor related cortical excitability is not driven by an aerobic exercise effect and is more indicative of a delayed neurotransmitter effect.

AbstractThe bactericidal effect of ozone at concentrations of 1 and 2 p.p.m. by volume, was tested on separately atmized resting cell suspensions of Aerobacter aerogenes, Bacillus megathreium, and Escherichia coli B impinged on Millipore filters. The exposure of each species required the use of 18 randomly selected filters containing impinged organisms. Of the 18 filters, 6 were used in the control. The temperature and the relative humidity of the ozone flow were approximately 25ºC and 20 per cent, respectively, while the flow-rate across each filter was 3 liters per minute. It was found that all of the organisms tested were completely destroyed by both 2 and 2 p.p.m. ozone within 2 minutes of exposure.Ball State UniversityMuncie, IN 47306

Different field tests are currently used in a wide extent in different levels of soccer teams. To be able to assess the players’ physiological status the tests must have high validity, reliability and external validity. Many different tests have been developt, but currently only five of these tests are most commonly used: Yo-Yo intermittent recovery test (YIRT), Yo-Yo intermittent endurance test (YIET), Multi-sprint-test, Beep-test and Cooper-test. Presently there is no definitive conclusion regarding which of these tests is most suitable for soccer players. Therefore the present study aimed to, on the basis of previous studies evaluate the advantages and disadvantages of the five most commonly used field test; to analyze the physiological requirements on soccer players with respect to their aerobic and anaerobic capacity; and last to compare among the five field tests and evaluate the validity of the field tests through comparison of field tests results with results from laboratory and soccer matches. During soccer match about 75-96 % of the energy is provided by the aerobic systems, while the rest, 4-25 %, is provided by the anaerobic systems. This fits approximately most of the results from both field tests and laboratory tests through measurement of either pulse, running distance, VO2max or lactate. Among the five tests, Yo-Yo tests (YIRT and YIET) has the best correlation to soccer match with respect to physiological demands on both aerobic and anaerobic capacities. Among the different Yo-Yo tests YIRT2 seems to be the best compared to YIET1, YIET2 and YIRT1.

Thesis (M. Ed.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 47-57).

Thesis (M.S.)--Rutgers University, 2009. / "Graduate Program in Nutritional Sciences." Includes bibliographical references (p. 99-107).

Thesis (M. Sc.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 68-75).

Thesis (M.A.)--Memorial University of Newfoundland, 2002. / Bibliography: leaves 116-122.

There is an increasing recognition that vascular disease risk is associated with a greater incidence of cognitive impairment and dementia. Such link is supported by the physiological observation that cerebral metabolism heavily relies on vascular supply of oxygen and energy substrates. Cerebral hypoperfusion which results from vascular dysfunction causes a mismatch between energy demand and supply and is associated with the pathological features of dementia, including the impairments of action potential generation and protein synthesis, glutamatergic excitotoxicity, and the deposition of cerebral amyloid-β proteins. In contrast, habitual aerobic exercise is an established strategy to ameliorate the risk factors for vascular disease and is increasingly recognized in improving cognitive function. Accordingly, the primary purpose of this dissertation study was to investigate whether the exercise-related improvement in cognitive function was attributable to ameliorated vascular function and risk factors for vascular disease. In order to address this as comprehensively as we could, both cross-sectional and interventional studies were conducted. The primary findings from the present study were as follows. In the cross-sectional study, a greater cognitive performance observed in endurance-trained adults was associated with higher levels of cerebral CO2 reactivity and brachial endothelium-dependent vasodilation and lower levels of central arterial stiffness and plasma insulin. In the interventional study, a 3-month aerobic exercise training intervention did not improve cognitive function although central arterial stiffness and brachial endothelium-dependent vasodilation made favorable changes. However, we found that the improvement in memory performance after aerobic exercise training was associated with the reduction in central systolic blood pressure. Taken together, a better cognitive performance observed in endurance-trained adults may not directly be attributable to greater vascular function because there were discrepant changes in cognitive and vascular functions after a 3-month aerobic exercise intervention. The correlation between the changes in memory performance and central systolic blood pressure is interesting but needs further investigation using a larger sample size. The discrepancy in the results between the cross-sectional and interventional studies could be explained by the duration of exercise training and/or the time it takes for the effect of improved vascular function to translate into cognitive function. / text

The purpose of this study was to investigate the effects of hydroxytyrosol (HT) supplementation on markers of mitochondrial biogenesis, aerobic capacity, and endurance exercise performance in recreationally active men. Sixty-one (n = 61) subjects (21.46 ± 0.22 yrs, 179.46 ± 0.79 cm, 78.91 ± 1.19 kg) consumed either a high dose (HI) HT supplement (150 mg HT), a low dose (LO) HT supplement (50 mg HT), or a placebo (PLA) every day for 6 weeks. Muscle biopsies from the vastus lateralis were obtained at baseline and after 6 weeks of supplement consumption and analyzed for markers of mitochondrial biogenesis: succinate dehydrogenase (SDH), citrate synthase (CS), and peroxisome proliferator-activated receptor ɣ coactivator (PGC)-1α. Subjects completed exercise testing on a bicycle ergometer at baseline and after 3 and 6 weeks of supplement consumption to measure changes in maximal aerobic power (VO2MAX), lactate threshold, respiratory exchange ratio (RER), substrate utilization, and endurance exercise performance on a 20 km time trial course. The primary findings were that HT supplementation increased muscle oxidative enzyme activity suggesting increased oxidative capacity. HT also increased time trial performance at midpoint and endpoint and this corresponded with an improvement in lactate threshold and a lower RER for the LO HT treatment. Time trial performance was also improved at endpoint for PLA, however, unlike LO an HI HT, this was accompanied by a significant increase in rating of perceived exercise (RPE) and not associated with improvements in muscle oxidative capacity. Our results indicate that HT ranging from 50 to 150 mg/day for 6 weeks can improve muscle oxidative capacity and aerobic performance, and suggests that HT may be used chronically to improve mitochondrial function. HT may be used as an effective means to increase mitochondria to improve exercise performance, and limit diseases associated with mitochondrial dysfunction such as cardiovascular disease, type II diabetes, and some cancers. / text