No description available.

The effect of heavy load carriage on pulmonary function at rest and on breathing pattern and lung volumes during graded exercise was studied. Fifteen males completed treadmill tests to measure VO2peak with and without a 25-kg pack. Subsequently, each subject completed short periods of treadmill walking in loaded and unloaded conditions at intensities equivalent to 55, 65, 75 and 85% of VO2peak. At rest, in the loaded condition, forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) both were reduced by 3% with no change in FEV1/FVC. During exercise with the pack, tidal volume (VT) and end-inspiratory lung volume (EILV) were reduced by 14 and 5%, respectively, while ventilation (VE) was maintained by a 9% increase in breathing frequency (Bf). Rating of perceived exertion (RPE) was always higher during the loaded trial, despite identical oxygen consumption (VO2) and heart rate (HR) responses. During graded exercise under heavy load up to 85% of VO2peak, breathing pattern is altered to maintain VE while respiratory mechanics were not altered.

Thesis (MAppSc in Physiotherapy)--University of South Australia, 1997

Thesis (MAppSc in Physiotherapy)--University of South Australia, 1996

Thesis (MAppSc in Physiotherapy) -- University of South Australia, 1998

Thesis (MAppSc in Physiotherapy)--University of South Australia, 1995

No description available.

No description available.

This thesis investigated the effect of exercise and the exercise setting on self-concept in the context of older women. Very little research in this area has focused on older women. At the same time it attempted to identify possible mechanisms underpinning exercise-induced change in self-concept, including the effect of the group and change in real and perceived body condition and real and perceived fitness. Adherence issues and the hierarchical structure of self-concept were examined in an exploratory manner. An extensive literature review was undertaken. It concluded with a preliminary exercise-self-concept model which would be used to explain and evaluate the thesis??? hypotheses. Two studies were undertaken. Study 1 validated the English version of the Self-perception in Exercise Questionnaire (SPEQ) (Sorensen, 1999) and examined relationships between exercise status, age, body size, and physical self-perceptions in a sample of older Australian women. The SPEQ was found to be a valid and reliable instrument to be used in Study 2 to measure self-perceptions relevant to exercise in older Australian women. Study 2, a randomised controlled trial, examined the effect of exercise and the exercise setting on older women???s self-concept. It comprises the main body of work for this thesis. It compared a group of older women exercising together in a group to a similar group of women who performed exactly the same exercise alone. Then both groups were compared to a similarly motivated group of women who did not exercise, but were waiting to start an exercise program. Using a pre-posttest design it measured exercise-induced change in self-concept, selfperceptions, satisfaction, and 13 physiological measures. Following a 12-week exercise treatment, the older women who walked regularly either alone or in a group thrice weekly experienced significantly improved total, physical, and social self-concept, more positive perceptions of their body and fitness, increased satisfaction with self and with life in general, and improved aerobic fitness compared to controls. When the three experimental conditions were compared, however, these outcomes were significant only for group exercise compared to controls; not for alone exercise compared to controls. Of greater importance, when the two exercise settings, walk alone and walk in a group, were compared, the women who walked in a group experienced significantly improved physical self-concept, satisfaction with life, and more positive perceptions of their body and fitness compared to the women who walked alone. Unexpectedly, aerobic fitness also increased significantly for the women who walked in a group relative to controls, but not for the alone walk condition. Taken together these findings suggest group exercise offers considerable psychological and aerobic fitness benefits to older women. These are valuable and unique findings. They are reinforced by the high adherence (91%) and participation rates (95%) achieved in the walk trial. Partial support was found for the proposed exercise-self-concept model and the hierarchical structure of self-concept was demonstrated. Perceived change accounted for more of the variance in self-concept than real body and fitness change. Effect sizes were larger for certain physical self-perceptions than for global self-concept. In conclusion, this thesis has extended current knowledge of exercise effects on selfconcept to older women, added a systematic exercise-self-concept review, added a useful instrument for measuring older women???s self-perceptions in exercise in future studies, and added to current knowledge of mechanisms underpinning improved self-concept following exercise. Exercise, moderate-intensity walking, was found to positively and significantly affect older women???s self-concept. The exercise setting differentially affected older women???s selfconcept; effects were significantly greater when the exercise was performed in a group with similar others. The group exercise setting and its effect on self-perceptions is suggested as a possible mechanism underpinning the positive exercise-self-concept association.

The ability to perform well during the sprint start and early acceleration phases of sprint running is critical. Many forms of training interventions are utilised to give a sprinter a competitive edge over their opponents in these particular phases. Despite this fact, there has been limited research on the technical and power type training strategies appropriate to improve sprint kinematics and the associated sprint performance in the sprint start and early acceleration phases. PURPOSE: To determine the best sprint start and early acceleration phase kinematic determinants, investigate the effect that load has on the kinematics of the sprint start and early acceleration performance and to determine how various physical characteristics may influence both resisted and unresisted sprint running. METHODS: Ten male track sprinters (mean ± SD: age 20 ± 3 years; height 1.82 ± 0.06 m; weight 76.7 ± 7.9 kg; 100 m personal best: 10.87 + 0.36 s {10.37 - 11.42 s}) attended two testing sessions. The first session required the athletes to sprint twelve 10 m sprints from a block start under unresisted and resisted (10% & 20% body mass) sled conditions. The second session required each athlete to complete an anthropometric assessment (height, mass, 3 bone lengths, 2 bone widths) and a variety of vertical (squat jump, countermovement jump, continuous straight legged jump) and horizontal (single leg hop for distance, single leg triple hop for distance) jump tests (3 trials each). Centre of gravity, joint and segment kinematics were calculated from 2D analysis utilising a kinematic analysis system (Ariel Performance Analysis System, U.S.A.). Means and standard deviations are presented for kinematic and performance measures. Pearson's product-moment correlation coefficients were employed to establish relationships between sprint start (block) performance variables and 10 m sprint performance. A linear regression analysis was used to quantify the relationships between the dependent variables (start performance and 10 m sprint time) and selected kinematic independent variables. ANOVA's with repeated measures were used to determine if there was a significant interaction between the kinematics under the various loaded conditions. A stepwise multiple regression and linear regression analysis were used for the prediction of unresisted and resisted sprint times from anthropometrical and functional performance measures. RESULTS: Mean horizontal block acceleration was identified as the start performance variable with the strongest relationship to 10 m sprint time. The most significant kinematic predictors of mean horizontal block acceleration were a large horizontal block velocity, short start time, and low thigh angle of the front block leg with respect to the horizontal at block takeoff. Sprint time over 10 m was best predicted by a large mean horizontal block acceleration (sprint start performance), increased angle of the front arm shoulder at step takeoff, and increased angle of front upper arm at step takeoff. Sprint start kinematics significantly altered as a result of resisted sled towing were start time (increase) and push-off angle from the blocks (decrease). Step length, stance time and propulsion time significantly increased, whereas flight time and flight distance significantly decreased under loaded conditions. A load of 20% body mass was revealed to be the better training load to utilise during resisted sled sprinting, especially for athletes who performed faster than 2.10 s for a 10 m sprint from a block start. The countermovement jump exercise was a strong predictor of both 10 m and 100 m sprint time. The continuous straight legged jump test was revealed to be a good predictor of resisted sprints over 10m.CONCLUSION: Consideration should be given to the technical training aspects of sprint start performance and forceful arm movements during step takeoff for improving sprint start and early acceleration sprint performance from starting blocks. These technical training aspects should also be supplemented with resisted sled towing with a load of 20% body mass and countermovement jump training to improve sprint ability.