An examination of the effects of a structured activity program on resting metabolic rate (RMR), physical activity, and dietary behavior is essential in gaining a better understanding of potential strategies that may be used in future exercise training programs. PURPOSE: To explore whether endurance training alters energy balance via changes in resting metabolic rate (RMR), daily energy expenditure (EE) and energy intake (EI). METHODS: Twenty-four subjects (17 females, 7 males; 21 + 0.3 years old) were assigned to one of two groups: 1) endurance (E; n = 12), or 2) active control (AC; n = 12). The E group completed 15 weeks of marathon training and the AC group maintained their usual exercise routine. Primary outcomes were measured pre- and post-training and included: anthropometric indices, RMR, EI, EE, and time to complete 1.5 miles (in minutes). Dietary intake and energy expenditure were also measured mid-training. RESULTS: Differences present among the groups at baseline included: the E group had significantly higher estimated VO2max values (as measured by the time to complete 1.5 miles) and higher energy expenditure rates (measured via accelerometer data) than the AC group. Post measurements revealed that both the E and AC groups significantly increased daily energy expenditure from baseline measures (p = 0.005) and decreased time to complete 1.5 miles (p = 0.022). After training, the E group significantly increased energy expenditure during the tenth week of training (p = 0.009). No significant relationships were observed between marathon training and body weight, resting metabolic rate, or energy intake. CONCLUSION: The results of the study suggest individuals following an intensive, marathon training program may experience an increase in EE without a concomitant increase in EI. They may also fail to see improvements in body weight or RMR. Additionally, the parallel changes in EE and EI, and the increase in VO2max observed in the AC, when compared with the E group, may indicate that an uncontrollable factor may have been involved.

Background, Rationale and General Purpose: Several seminal observations suggest that AMPK mediates vascular tone: 1) in endothelial cell culture and in vitro isolated protein experiments, activation of AMPK stimulates nitric oxide (NO) production via phosphorylation of endothelial nitric oxide synthase (eNOS), 2) stimuli associated with AMPK activation relax isolated vascular smooth muscle preparations from healthy animals, and 3) acute activation of AMPK in vivo induces hypotension in normotensive animals, an effect that could be indicative of reduced vascular tone. Together these findings prompt the logical hypothesis that acute activation of AMPK induces relaxation that is both endothelium-, NO-dependent and also vascular smooth muscle dependent; however the direct effects of AMPK activation on the regulation of vascular tone in the context of intact healthy arteries in vitro or in situ have not been tested. AMPK activation is dysregulated in essential hypertension and aging, conditions both characterized by vasomotor dysfunction. The integrity of AMPK-mediated vasomotor effects has not been evaluated in any model of vascular dysfunction or in the presence of AMPK dysregulation, and so it is unknown if or to what extent, activation of AMPK alters vascular tone in vessels with these impairments. The mechanisms of AMPK-mediated vasomotor effects have also not been delineating in healthy or dysfunctional arteries. Studying basic vascular signalling mechanisms in both healthy and dysfunctional models is important for understanding physiological function and regulation of vascular tissue, as well as to understand vascular pathology and aid in the development of therapeutic interventions. Collectively these considerations present compelling reasons to investigate the role of AMPK in vasomotor function in health and disease. The unifying purpose of this thesis was therefore to investigate the role of AMP-activated protein kinase in regulating vascular tone in arteries of healthy, hypertensive and aged rats. Experimental Approach and Main Findings: The global objective of the thesis is satisfied by four main studies that utilize a combination of in vitro isolated artery preparations to assess vasomotor function, biochemical analyses and in vivo hemodynamic assessments. In Study 1, we characterize the basic nature of the vasomotor response generated acutely by the pharmacological AMPK activator AICAR in vitro in isolated aorta of normotensive (Wistar-Kyoto rats; WKY) and hypertensive rats (Spontaneously Hypertensive rats; SHR), and the mechanisms mediating these responses. In these experiments, acute activation of AMPK using AICAR induced dose-dependent relaxation of isolated, precontracted arteries from WKY and SHR that was dependent in part on both the endothelium and vascular smooth muscle, and vasorelaxation to AICAR was enhanced in aortic rings of SHR versus those of WKY. In WKY, the endothelium-dependent component of relaxation to AICAR was solely NO-mediated, while in SHR it was dependent on both elevated NO-bioactivity and blunted COX-dependent contraction. In Study 2, we investigate the mechanisms responsible for AMPK-mediated inhibition of endothelium- and cyclooxygenase-dependent vasocontraction in aorta from WKY and SHR (a response enhanced in arteries of hypertensive rats that contributes to vasomotor dysfunction). Pre-activation of AMPK blunted endothelium-dependent contractions to acetylcholine in isolated, non-precontracted WKY and SHR aortic rings. The mechanisms accounting for this effect of AICAR were endothelium-specific, occurring via inhibition of the ACh-stimulated production/release of 6-keto-prostaglandin F1α, the major product of prostacyclin, which is the key prostanoid responsible for endothelium-dependent contractions in aorta of WKY and SHR. AMPK activation had no effect on vascular smooth muscle responsiveness to TP-receptor agonists, ruling out a contribution of vascular smooth muscle mechanisms. In Study 3, we examine responses and mechanisms associated with acute pharmacological AMPK activation on vascular tone of isolated mesenteric resistance arteries in vitro, and on in vivo hemodynamics in WKY and SHR. These experiments revealed that administration of AICAR acutely in vivo acutely reduced blood pressure by ~70mmHg in SHR and this effect was partly NO-dependent. In contrast, AICAR had no effect on blood pressure in WKY. Activation of AMPK also produced vasodilation of isolated, precontracted WKY and SHR resistance mesenteric arteries in vitro, and this was dependent on NO to a greater extent in SHR than in WKY. Together, the parallel reductions in blood pressure in vivo and relaxation of isolated arteries in vitro support reduced vascular resistance as a potential explanation for the in vivo blood pressure effects. Finally, Study 4 characterizes the basic vasodilatory responses to acute AMPK activation and mechanisms associated with these responses in aorta from aged animals and their young counterparts (male Sprague Dawley rats) to glean insight using an additional model of vasomotor dysfunction. In this study, acute activation of AMPK using AICAR generates relaxation in a dose-dependent manner that is partly endothelium-, NO-dependent and partly reliant on vascular smooth muscle in precontracted aorta of both young and aged rats. Similar to the findings of Study 1 in SHR versus WKY, vasodilatory response to AICAR were also enhanced in dysfunctional aorta of aged rats versus healthy aorta of young animals. Other agents shown to activate AMPK in other tissues and models, the anti-diabetic drug metformin and the polyphenol resveratrol, generated varying amounts of relaxation in vascular smooth muscle of young and aged aortic rings. These effects were only associated with AMPK activation in rings treated with metformin but not resveratrol. Conclusions and Perspectives: These findings are the first to characterize the vasomotor responses generated by acutely activating AMPK in intact arteries of any hypertensive or aging model, and to delineate mechanisms mediating these responses in healthy and dysfunctional vessels. Despite vasomotor dysfunction and dysregulated AMPK activity in arteries of hypertensive and aged rats, acute AMPK activation still generates robust relaxation responses via endothelium- and NO-dependent relaxation, inhibition of enhanced endothelium-dependent contractions in SHR, and direct relaxation of the vascular smooth muscle; effects that would aid in reversing the dysfunctional characteristics of arteries from these animals, and may recommend AMPK as a useful therapeutic target for interventions aimed at improving vasomotor function. Future studies will be necessary to reveal whether AMPK plays a role in generating acute changes in vessel tone induced by AMPK-activating physiological stimuli in situ (i.e. such as shear stress during exercise). Together these data continue to support AMPK as a novel regulator of vascular tone, yield valuable, novel, mechanistic insight into AMPK-mediated regulation of vasomotor function in arteries during health, disease and aging, and highlight the need for continued investigation into a vasoregulatory function for AMPK in health and disease.

Thirty-one trained male subjects performed one-repetition maximum lifts (IRM's) on three Hammer Strength Externally Loaded Machines and three comparable Free Weight Exercises. All tests were counterbalanced and randomly assigned. Subjects performed two 1RM tests during each lab session, with at least 48-72 hours of recovery between each. IRM's were recorded as the greatest amount of weight lifted with proper technique. 1RM data was used to (1) determine the relationship between 1RM performed on Hammer Strength machines versus Free Weights and (2) to develop regression equations that can accurately predict IRM's when switching from one exercise modality to another. Statistics revealed significant differences (p<0.05) between IRM's performed on the Hammer Strength equipment as compared to its counterpart free weight exercise. For all exercises, IRM's were significantly greater/higher on Hammer Strength equipment. Regression equations were developed for all exercises, except when predicting the Hammer Strength shoulder press and the Hammer Strength Preacher Curls from their free weight counterparts, where no variables existed that could significantly predict their respective IRM's.

Caffeine is the most widely consumed drug in the world. Research has suggested that caffeine can enhance aerobic performance. However, its benefits in the resistance training world are not fully understood. Due to caffeine's ability to alter pain perception and the onset of peripheral fatigue it may positively affect performance. This study examined the effects of caffeine on muscular strength, determined by the number of successfully completed reps at 85% of 1RM bench press. Fifteen recreationally trained males were tested for their 1RM on bench press. Subjects completed 3 randomized, double blind tria ls at 85% of their 1RM to failure after receiving caffeine, a placebo, or no treatment. Successful reps were recorded. Data was analyzed using a within group ANOVA (p = 0.05) to compare the differences in reps between trials. No significant differences were found between trials; however the mean number of reps completed was greater for the caffeine vs. placebo trials (7.27 vs. 7.2), suggesting no negative effect occurred as well. Further research is needed utilizing more complete training bouts and lower intensity/ higher repetition training.

The Wilderness Education Association has seen and answered the need to train outdoor leaders. It has provided a wide range of courses and opportunities for future outdoor leaders to learn and practice their skills. It is important to examine the effectiveness of these courses and how they effect course participants. This study focused on the perceived changes by students in their leadership skills as a result of the Wilderness Stewardship Course. This study was conducted during a Wilderness Education Association Wilderness Stewardship course offered at Western Kentucky University. The established Leadership Skills Inventory, developed by Frances Karnes and Jane Chauvin, was used in evaluating student leadership perceptions. The inventory requires individuals to respond to questions that have been separated into 9 leadership categories. Strengths and weaknesses of the individuals are measured by their answers. The categories include fundamentals of leadership, written communication, speech communication, decisionmaking, group dynamics, problem-solving, personal development, and planning skills. Students were given the inventory as a pre and posttest and the results were analyzed using a paired t-test. The results indicated a significant change in student's perception of skills in four areas. They areas include fundamentals of leadership, speech communication skills, character-building skills and group dynamic skills. Length of course, direct teaching on subjects, and opportunities to practice skills provided opportunities to develop skills in the above mentioned areas.

Social identity theory explores the process of self-identifications based upon perceived shared commonalities with others in order to positively affiliate with group membership and accounts for inter-group and intra-group behaviors (Deaux, 2001; Hogg & Abrams, 1999; Tajfel, 1982). Social identity is also dependent upon environment and situation dynamics (Turner, 1982). African American females are at risk for high levels of physical inactivity. Researchers have suggested the use of frameworks that move investigations beyond assessing social aggregates such as race and gender to understand why this is true. Racial identity, gender-role identity, and exercise identity (derived from social identity theory) provide a framework to go beyond categorical labels. The purpose of this dissertation was to explore intersections among racial identity, gender-role identity, and exercise identity on the physical activity participation of African American females, extending the current research regarding determinants of physical activity participation for African American females. The first study used quantitative methods to investigate relationships among racial identity, gender-role identity, exercise identity, physical activity participation, and perceived social support within an African American college female sample population. Results indicated females who exercised more often had a stronger sense of exercise identity, displayed masculine gender-role identity and had higher perceived levels of social support. Perceived friend social support predicted exercise identity and frequency of physical activity participation. Study two qualitatively explored the intersection of racial identity, gender-role identity, and exercise identity of African American females who were considered regular exercisers by running group affiliation. The following themes emerged: 1) group membership advantages; 2) exercise as a catalyst for change; 3) perceived obstacles to physical activity. The findings indicated that exercise identity is more salient than racial and gender-role identities. Perceived cultural barriers such as hair, food, and body image had a diminished affect when exercise was accepted as part of identity. Taken together, findings support the conclusion that a focus on developing a strong exercise identity through cultural lenses of other identities such as race and gender is an important factor in efforts to promote physical activity in diverse populations.

Quality physical education can positively influence students emotional development, specifically their perceptions of competence, self-esteem, and self-concept. Unfortunately, girls often become less engaged and involved in physical education as they grow older and consistently report lower physical self-concepts than males. Physical self-concept is associated with multiple positive outcomes, yet there is only speculation addressing why females report lower physical self-concepts than males in physical education. The overall purpose of this dissertation was to investigate potential explanations for gender discrepancies in physical self-concept among physical education students. One qualitative and one quantitative research study was conducted to address this issue. The purposes of the qualitative study were to capture female students personal interpretations of physical self-concept, frame of reference, and the physical education environment. Results indicate that the girls enrolled in same-sex physical education classes perceived the coed environment negatively and experienced pressure regarding physical ability and appearance. Competition in physical education received significant attention and was desirable only in appropriate levels and contexts. Results supported that the students used multiple sources of information in physical self-concept development. Participants conformed to traditional gender norms and viewed males as more aggressive and physically dominant than females. In addition, all participants perceived same-sex physical education as a more desirable setting. The purposes of the quantitative study were to investigate a BFLPE and moderating effects of class type among female students in physical education. It was hypothesized that: a) individual ability would positively predict sport self-concept and class-level ability; b) class-level ability would negatively predict sport self-concept (also known as a BFLPE); and c) class structure (e.g. same sex, coeducational) would moderate the BFLPE in physical education. Results provided evidence that participants in both class types experienced a BFLPE. Class type did not increase or decrease the BFLPE for these students, indicating that the girls in these coed classes were not at an increased risk for experiencing negative consequences to their sport self-concept as a result of a BFLPE. Overall, results provide additional information of physical self-concept development among adolescent females in physical education. Implications for practitioners and suggestions for future research are included.

Manual muscle tests (MMTs) are frequently used in clinical settings to evaluate a specific muscle’s function and strength in a position at which this muscle is believed to be most isolated from other synergists and antagonists. It is necessary for a muscle to be tested in a state of isolation (as much as is physiologically possible), as interpretation of strength and function can be compromised by the contributions of other active muscles. In the present study, electromyographic activation of 14 shoulder muscles was assessed in 12 males during 29 shoulder exertions. Maximal isolation ratios defined which of these exertions most isolated the rotator cuff muscles. Results confirmed the appropriateness of nine clinical MMTs in isolating the rotator cuff muscles, but suggested that several other exertions were equally appropriate in isolating these muscles. Forces produced during isolation exertions can be compared to patient exertions to promote more objective MMT grading.

The purpose of this study was to examine the effects of exogenous peroxynitrite (ONOO-) on the cardiac isoform of the sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA2a) and to determine if overexpression of heat shock protein 70 (Hsp70) could protect SERCA2a function. To characterize the interaction between SERCA2a and Hsp70, cDNAs encoding each protein were co-transfected in human embryonic kidney cells (HEK-293) using the calcium-phosphate technique. Western blotting confirmed the expression of SERCA2a and a ~1.9-fold overexpression of Hsp70 in HEK-293 cells. ONOO- was added chronically (250 μM bolus each minute for 10 minutes) to co-transfected HEK-293 cells in culture. Maximal Ca2+-ATPase activity (Vmax) was assessed on microsomal fractions isolated following exposure to ONOO-. Vmax was reduced by ~20% in HEK-293 cells transfected with SERCA2a alone (S2a-pMT2). When Hsp70 was co-transfected with SERCA2a (S2a-Hsp70), Vmax was fully protected following incubation with ONOO-. Western blot analysis showed that there were no changes in FITC binding capacity and 3-nitrotyrosine content in any of the groups. However, overexpression of Hsp70 prevented oxidation of SERCA2a, as assessed by reactive carbonyl content, following exposure to ONOO- when compared to S2a-pMT2. In addition, SERCA2a aggregation was lower compared to S2a-pMT2 groups under both control and ONOO- conditions. Co-immunoprecipitation of SERCA2a and Hsp70 confirmed that Hsp70 physically interacts with SERCA2a under all conditions. These results suggest that Hsp70 physically binds to SERCA2a and prevents oxidation and aggregation of SERCA2a, thus preserving enzyme activity.

Background: Osteoarthritis (OA), the most common form of arthritis, is a disorder that affects bi-articular synovial joints and is characterized as the focal loss of articular cartilage with changes to the subchondral and marginal bone, synovium and para-articular structures. Biomechanical factors such as obesity, joint loading, joint injury, joint deformity, level of sports participation, occupational factors, and muscle weakness specifically affect joint loading which influences local OA development. One way to assess the effect of altered loading patterns on a joint is to examine changes following joint injury. An appropriate model for this purpose is the anterior cruciate ligament (ACL) rupture in the knee joint. Recent evidence has shown that some ACL-D subjects are able to perform activities at levels similar to those of normal subjects. Termed ‘Copers’, these individuals demonstrate greater knee stability than other ACL-D subjects who are considered ‘Non-Copers’. Therefore, the purpose of this study was to evaluate the dynamic control strategies used by ACL-D Copers and Non-Copers during a stair climbing task, and compare them to a healthy population as a means to identify possible susceptabilities to OA. Methods: A total of 20 participants were collected including 10 (5 male and 5 female) Healthy controls, 5 (2 male and 3 female) ACL-D Copers, and 5 (1 male and 4 females) ACL-D Non-Copers. The Healthy group had an average mass of 75.9 kg ±16.1 kg and an average height of 174.3 cm ±12.1cm, while the Copers group had an average mass of 71.7 kg ±6.2 kg and an average height of 170.8 cm ±5.6 cm, and the Non-Copers group had an average mass of 71.3 kg ±13.1 kg and an average height of 168.7 cm ±4.8 cm. ACL-D subjects were classified as either a Coper and Non-Coper based on a screening examination prior to the evaluation.The stair climbing task involved each subject completing 20 stair-climbing trials (10 ascent and 10 descent). Kinematic and kinetic outcomes were collected on the lower limbs, as well as,electromyography (EMG) of the tibilais anterior, medial and lateral gastrocnemius, vastus lateralis, vastus medialis, semitendinosus, and biceps femoris muscle group were collected bi-laterally. A one-way analysis of variance (ANOVA) was used to test each outcome’s statistical significance (α= 0.05). Results and Discussion: During ascent the Non-Copers and Copers group completed the task with greater knee flexion than the healthy group (although not significant), while during descent the Non-Copers maintained approximately 5 degrees greater flexion than the other groups. A significant difference was observed with the moment about the knee (flex-ext) between the Healthy group and the Non-Copers group during the late stages of stair ascent with the healthy group maintaining a flexor moment and the Non-Copers group using an extensor moment. This extensor moment correlated with the increase of quadriceps activity among the Non-Copers which may lead to instances of knee joint instability. The Non-Copers group had increased activity of the hamstring muscle group without any attenuation in the quadriceps muscles. This will most likely increase the forces acting on the knee joint. Since, the knee is at greater flexion with an increased amount of forces, the Non-Copers may be at a greater risk articular cartilage breakdown. Throughout the majority of descent we saw an elevated amount of hamstring activity in the Non-Copers group at greater knee flexion angles as a potential means of controlling displacement of the tibia. This increase in hamstring muscle activity by the Non-Copers, without any significant decrease in quadriceps activity, places greater forces on the knee at different knee angle, when compared to the healthy group and may promote the onset of osteoarthritis. The Non-Copers also had increased moments about the knee joint for the majority of stance in both the flexion-extension plane and the abduction-adduction plane, when compared to the healthy group.