Juvenile idiopathic arthritis (JIA) is a common chronic disease of childhood. Children with JIA have lower peak oxygen consumption (V0₂ peak) than healthy children. In order to examine the cardiorespiratory response during aerobic exercise and the anaerobic to aerobic ratio (metabolic index), maximal exercise tests were performed in JIA subjects and age- and sex-matched controls (CON). Thirteen children aged 10 to 17 years with JIA and 9 CON participated. Peak powe r(watts, W) and total work (Joules, j) were determined with the Wingate anaerobic cycling test. VO₂ peak was measured by a maximal staged exercise test on a cycle ergometer. Cardiac output (CO, liters/minute) was measured with Doppler echocardiography. Arterial — mixed venous oxygen index (A-V0₂) and systemic vascular resistance (SVR) were calculated. Patient questionnaires included habitual activity, visual analog scale for joint pain and the childhood health assessment questionnaire. Physician completed data included active joint count and articular severity index. Compared to CON and reference age-matched norms, JIA subjects had lower aerobic fitness. VO₂ peak in JIA was 31.3 ml/min/kg (20.2-49.9), Z score -1.4 (-.06--2.4) and in CON was 47.9 ml/min/kg (32.7-54.1), Z score of -0.17 (-1.6-.87). [p = 0.013 V0₂ peak, p=0.011 Z score]. There were no significant differences in CO, A-V0₂ or SVR buttrends towards lower CO and higher SVR in JIA subjects were observed. During anaerobic exercise JIA subjects completed less total work (168.5 j/kg (107-252) JIA, 224 j/kg (180-248) CON, p=.036) but had similar peak power (9.7 W/kg (5.6-13.7) JIA, 11.3 W/kg (9.8-14.5) CON, p=.095). The metabolic index did not differ between JIA and CON. There was no significant correlation between disease activity, function and fitness measures in JIA subjects. Children with JIA have moderate impairments in aerobic fitness. CO and A-V0₂ during aerobic exercise did not significantly differ between JIA subjects and CON. Anaerobic fitness was mildly impaired with less total work completed by JIA subjects. Further research with larger numbers is required to determine factors contributing to limited fitness in JIA.

Thesis (Ph.D.)--Auburn University, 2007. / Abstract. Includes bibliographic references (ℓ.102-121 )

Thesis (M.S. Ed.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaves 125-134). Also available via the Internet.

Thesis (M.S. Ed.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaves 81-87). Also available via the Internet.

Thesis (M.A.)--San Jose State University, 2003. / Includes bibliographical references (leaves 57-62). Also available online (PDF file) by a subscription to the set or by purchasing the individual file.

Thesis (M.S.)--University of Wisconsin--Madison, 1968. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (M.A.)--San Jose State University, 2003. / Includes bibliographical references (leaves 57-62).

Juvenile idiopathic arthritis (JIA) is a common chronic disease of childhood. Children with JIA have lower peak oxygen consumption (V0₂ peak) than healthy children. In order to examine the cardiorespiratory response during aerobic exercise and the anaerobic to aerobic ratio (metabolic index), maximal exercise tests were performed in JIA subjects and age- and sex-matched controls (CON). Thirteen children aged 10 to 17 years with JIA and 9 CON participated. Peak powe r(watts, W) and total work (Joules, j) were determined with the Wingate anaerobic cycling test. VO₂ peak was measured by a maximal staged exercise test on a cycle ergometer. Cardiac output (CO, liters/minute) was measured with Doppler echocardiography. Arterial — mixed venous oxygen index (A-V0₂) and systemic vascular resistance (SVR) were calculated. Patient questionnaires included habitual activity, visual analog scale for joint pain and the childhood health assessment questionnaire. Physician completed data included active joint count and articular severity index. Compared to CON and reference age-matched norms, JIA subjects had lower aerobic fitness. VO₂ peak in JIA was 31.3 ml/min/kg (20.2-49.9), Z score -1.4 (-.06--2.4) and in CON was 47.9 ml/min/kg (32.7-54.1), Z score of -0.17 (-1.6-.87). [p = 0.013 V0₂ peak, p=0.011 Z score]. There were no significant differences in CO, A-V0₂ or SVR buttrends towards lower CO and higher SVR in JIA subjects were observed. During anaerobic exercise JIA subjects completed less total work (168.5 j/kg (107-252) JIA, 224 j/kg (180-248) CON, p=.036) but had similar peak power (9.7 W/kg (5.6-13.7) JIA, 11.3 W/kg (9.8-14.5) CON, p=.095). The metabolic index did not differ between JIA and CON. There was no significant correlation between disease activity, function and fitness measures in JIA subjects. Children with JIA have moderate impairments in aerobic fitness. CO and A-V0₂ during aerobic exercise did not significantly differ between JIA subjects and CON. Anaerobic fitness was mildly impaired with less total work completed by JIA subjects. Further research with larger numbers is required to determine factors contributing to limited fitness in JIA. / Education, Faculty of / Kinesiology, School of / Graduate

The purpose of this study was to examine the changes in the ventilatory (VT) and lactate (LT) thresholds and VO₂max following prolonged aerobic exercise. Six well-trained distance runners (T:age=25.2 yrs, Ht=170.0 cm, Wt=65.0 kg, VO₂max=59.6 ml •kg⁻¹•min⁻¹) and six untrained (UT:age=25.3 yrs, Ht=180.3 cm, Wt=79.2 kg, VO₂max=46.8 ml•kg⁻¹•min⁻¹) males were studied on two occasions seven days apart. The initial evaluation involved a continuous horizontal treadmill test with a starting velocity of 2.22 m•s⁻¹, which was increased by 0.22 m•s⁻¹ each minute until fatigue. Expired gases were continuously sampled and analyzed by a Beckman Metabolic Measurement Cart. Measurements were processed by a data acquisition system (HP 3052A), which determined respiratory gas exchange variables every 15 seconds. Blood lactate measurements were taken via an indwelling catheter during the last 10 sec of each minute of work. VT and LT were determined by visual inspection of the excess CO₂ elimination and lactate curves, respectively. Seven days later the subjects repeated the treadmill test preceded by a 60 minute treadmill run at a heart rate corresponding to their LT. The physiological measurements recorded during the first session were repeated. There were significant (p<0.10) reductions in VO₂max, LT, VT, and total treadmill time on the VO₂max test (TTT) in the T group (59.6 to 56.9 ml •kg⁻¹•min⁻¹, 9.6 to 9.3 mph , 8.9 to 8.2 mph , and 925.0 to 882.5 sec, respectively). VO₂max, LT, VT, and TTT were reduced in the UT group (46.8 to 45.0 ml•kg⁻¹•min⁻¹ 7.7 to 7.6 mph, 8.0 to 7.2 mph, and 730.0 to 652.5 sec, respectively), however, only VT and TTT were reduced significantly (p<0.10). Although the groups were significantly different (p<0.05) in the initial physiological measures due to training status, there was no change in the rate of decline in VO₂max, LT, VT, or TTT when the UT group was compared to T. As LT and VT are affected by prolonged aerobic exercise it is questionable whether these thresholds can be used with confidence to predict endurance performance in events up to 60 min duration for well-trained and recreational athletes. / Education, Faculty of / Curriculum and Pedagogy (EDCP), Department of / Graduate

The efficacy of an aerobic conditioning program (jogging) in modifying self-reported chronic intermittent stress is compared to stress-innoculation training (self-statement modification) and a waiting list control group. Guiding this research is a transactional model of stress. The participants were community residents; 48 were females and 25 were males. Therapy sessions were conducted over a 10-week period with subjects meeting in groups for 1 1/2 hours per week and also completing homework assignments and activities. The State and Trait Anxiety Inventories, the Tension Thermometer, a Thought-listing Technique and a Self-efficacy Scale were administered at pre, post, and three-month follow-up. In addition, a submaximal bicycle ergometer test was utilized to predict maximum oxygen uptake (a measure of cardiovascular fitness). Multivariate analyses of variance indicate that both the aerobic conditioning program and the stress-innoculation training were effective in reducing self-reported anxiety and increasing self-efficacy. These changes were maintained three months after completing the program. Subjects who experienced stress more cognltlvely than somatically reduced their level of stress from pre- to post-testlng significantly more than those who experienced stress more somatically, regardless of treatment condition. However, from post to follow-up the somatic subjects continued to improve while the cognitive subjects stayed approximately the same. Compared to the waiting list control group, subjects' positive self-statement ratings increased significantly from pre- to post-testing for the stress-inoculation group. Subjects' self-statement ratings and judges self-statement ratings changed differentially between groups and over time. Subjects in the aerobic conditioning program improved their cardiovascular fitness compared to the stress-inoculation and waiting list groups. Participation in an aerobic conditioning program was found to be a viable alternative to stress-innoculation training as a stress-management treatment. Although the pattern of changes differed between treatment groups and among types of individuals from pre- to post-testing on some measures, at three-months follow-up few differences were found between treatment groups. / Graduate and Postdoctoral Studies / Graduate