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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.
51

The effect of banked-curves on running mechanics : plantar foot pressures

Murias, Juan Manuel. January 2006 (has links)
The purpose of this study was to investigate the dynamic patterns of pressure distribution of curved running with and without banked surfaces at two speeds. Seven male elite runners ran at 3.8 m/s and 7.0 m/s in three different conditions: (1) straight, and along a curve with either (2) no side inclination or (3) an inclination of 19%. Running speed significantly affected peak pressure for plantar foot regions (p<0.05); however, few significant main effects were found for surface running condition or foot side. Center of pressure displacement showed similar patterns in both the medial-lateral and heel to toe excursion regardless the running condition, speed, or foot side. Future study needs to reduce measurement variability as well as to consider other dynamic foot-to-shoe components such as shear stresses.
52

Dissociating the valence-dependent neural and genetic contributions to decision making under risk

Haynes, Michael Ryan January 2012 (has links)
No description available.
53

The neural basis of frustration

Yu, Rongjun January 2011 (has links)
No description available.
54

Recovery metabolism following exercise above and below the anaerobic threshold

Diotti, Kristin A. January 2003 (has links)
This study determined the effects of exercising above (LATabove) and below(LATbelow) the lactate threshold, upon excess post-exercise oxygen consumption (EPOC) magnitude and duration among average fit females. Thirteen females underwent testing over a nine-day period (5 visits). Resting metabolic rate (RMR) was assessed over two days. A ramp cycle test determined peak V02 and LAT. Blood samples, ventilatory, and heart rate measurements were recorded during rest, exercise, and recovery. On separatedays, volunteers exercised 10% LATabove and LATbelow expending 300 kcals. Afterwards,heart rate, RER, and V02 were measured until within ± 5% of the baseline RMR. EPOC duration was significantly greater for LATabove (61.49 + 8.73 min) than LATbelow (30.72 + 4.81 min). EPOC magnitude was also significantly greater LATabove (24.29 + 3.67 kcals) than LATbelow (13.28 ± 2.10 kcals). This study demonstrated exercising at LATabove adds an additional energy cost component to the recovery dynamics. / School of Physical Education
55

The effect of progressive resistance strength training exercise on serum growth hormone and testosterone in young and elderly men

Brown, Robert G. January 1987 (has links)
The purpose of this study was to observe the response of serum hormones to a progressive resistance strength training program. Basal levels of serum growth hormone and total testosterone were measured before and after a 12-week strength training program in 8 young men (mean age= 23 years) and 13 elderly men (mean age= 63 years). The response of growth hormone and testosterone to an acute bout of strength training exercise was also measured. Changes in lean body mass, percent fat, fat weight, VO2max and girth measurements were determined.Sessions were started with walking and static stretching exercises for the major muscle groups. This was followed by 45-60 minutes of isotonic strength training exercise which consisted of the leg-press, leg-extension, leg-curl, torso extension, bench-press, pull-down, pull-over, horizontal arm adduction, arm adduction, and modified sit-ups on an abdominal platform. Subjects were told to increase weight at a station when they could successfully complete three sets of ten repetitions at that station. At weeks 2 and 12 of the study subjects were strength tested at the leg-press, leg-extension, and bench-press stations. Strength was measured as the most weight that could be lifted for six repetitions. Blood samples were drawn from an antecubital vein pre and post training, and before, immediately following and 15 minutes after an exercise session.There was a significant increase (p <0.001) in strength for both groups for the leg press, leg extention and bench press. However, the young group was significantly stronger (p <0.001) than the elderly group in both pre and post test for all muscles measured. There was a significant increase (p <0.01) in lean weight in the elderly group which was correlated with increased strength on the leg press, leg extension and bench press on the post test. There was a significant increase (p <0.05) in growth hormone for both groups in response to an acute bout of exercise on both the pre and post test with the rise being significantly higher (p <0.025) in the young group. The increased strength in the young group correlated positively with increased serum growth hormone following an acute bout of exercise on the post test. There was no significant change in serum testosterone in response to an acute bout of exercise in either group. Basal levels of growth hormone and testosterone did not change.
56

The effects of revolution rate on cycling efficiency

Jack, Martha Louise January 1975 (has links)
The purpose of this study was to examine the effects off revolution rate (i.e. gear ratio) on cycling efficiency and the energy cost of performance. A group of five trained cyclists performed ergometerr rides at either 60, 90, or 120 rpm and a constant absolute workload. Energy expenditure was determined during each minute of rest,-exercise, and recovery. Gross and net work efficiencies were calculated using several computational methods. Results showed that energy input increased as the rate of cycling increased. Gross and net resting baseline efficiencies decreased and net free wheeling baseline efficiency remained constant with increasing rpm. The increased energy demand with increased rpm was attributed to the increased cost of moving the legs and not to overcoming the resistance. It was concluded that the fastest performance ..s achieved when the energy demand is the greatest for the force exerted on the pedals and the oxygen debt could be tolerated for the duration of the race. Within the limitations of the study, at a constant work output the greatest muscular efficiency was achieved at low revolution rates. Although the net free wheeling efficiencies remained unchanged with increasing rpm, in practical terms these values did not reflect the total energy cost to the rider.
57

Effects of physical training on the heart rate and electrocardiographic response to sudden exertion

Elger, David H. January 1979 (has links)
Five policemen (26-46 years) participated in a Police Fitness Program lasting for 13 to 16 weeks. They either jogged or combined walking and jogging for a minimum of two miles per session until the time of the post test. As a result, all of the officers reduced their percentage of body fat, and four of the five policemen increased their maximal oxygen consumption. Training had no effect on the initial heart rate response to a fifteen second sudden exertion run on the treadmill at nine mph., twenty percent incline. The rate of recovery, however, was improved in all subjects. No electrocardiographic abnormalities were observed either before or after training. Because a limited number of subjects completed the study, the amount of data was insufficient to make any conclusive statements about the effects of physical training on the heart rate and electrocardiographic response to sudden exertion.
58

The behavioral and neural correlates of bimodal selective and divided attention to incongruent audiovisual events /

Johnson, Jennifer Adrienne. January 2007 (has links)
Humans live in a world rich in multisensory information. Often information reaching one sense is completely unrelated to information reaching another sense; that is, they are spatially and temporally incongruent. The goal of the research presented in this thesis was to elucidate the behavioral and neural bases of attention to incongruent audiovisual information. Five issues were addressed: (1) developing an appropriate behavioral paradigm to test bimodal attention, (2) understanding the role of crossmodal suppression in unimodal attention, (3) exploring the interaction of auditory and visual sensory cortex during bimodal selective attention, (4) exploring the role of fronto-parietal networks in bimodal selective attention, and (5) exploring the neural correlates of bimodal divided attention. Two different behavioral paradigms demonstrated that attended information was remembered better than unattended information. Functional magnetic resonance imaging (fMRI) revealed that crossmodal suppression of sensory cortex subserving a non-presented modality occurred consistently during unimodal attention tasks, and increased with attentional demand. During bimodal selective attention, activity was often enhanced in sensory cortex subserving an attended modality and suppressed in sensory cortex subserving an unattended modality, both compared to a bimodal passive baseline. This interaction depended in part on attentional demand and the nature of the stimulus information. No prefrontal regions were consistently activated by bimodal selective attention; however, dorsolateral prefrontal cortex (DLPFC) was recruited during one of the bimodal divided attention paradigms. Furthermore, temporary inactivation of the DLPFC using transcranial magnetic stimulation (TMS) led to decreased bimodal divided attention performance using the same paradigm. However, using a different bimodal divided attention paradigm, DLPFC was not recruited and instead ventrolateral prefrontal cortex (VLPFC) showed task-induced deactivation. This divergence is explained by the unique requirements of the two bimodal divided attention paradigms. Overall, these findings provide improved understanding of how humans process and attend to multisensory information, and raise several questions for further investigation.
59

Metabolic cost of aerobic dance circuit training

Audet, Diane January 1992 (has links)
This study was undertaken to characterize the oxygen consumption and heart rate responses of subjects during laboratory simulated aerobic dance circuit training sessions. Sixteen female subjects performed six randomly assigned 30-minute aerobic dance circuit training protocols. Oxygen consumption and heart rate responses were monitored in response to changes in three independent variables which were: interval duration, leg involvement and fitness level. Results revealed that the different interval durations generated significantly different oxygen costs. Also, it was found that in relative terms (% of max VO$ sb2$), the low fitness group (max VO$ sb2 $ 45 ml/kg.min). Furthermore, it was found that the involvement of deep knee bends during the resistance training segment of the circuit significantly increased the oxygen cost when the resistance training segments were compared. Finally, the results showed that exercise intensity was overestimated when using percentage of max HR.
60

A kinematic description of the ankle during the acceleration phase of forward skating /

Kirchner, Gary John. January 1986 (has links)
No description available.

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