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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.
161

THE CLINICAL USEFULNESS OF VECTOR CODING VARIABILITY IN FEMALE RUNNERS WITH AND WITHOUT PATELLOFEMORAL PAIN

Cunningham, Tommy Joseph 01 January 2012 (has links)
It has been suggested that Patellofemoral Pain (PFP) may be the result of a coordinate state which exhibits less joint coordination variability. The ability to relate joint coordination variability to PFP pathology could have many clinical uses; however, evidence to support clinical application is lacking. Vector coding’s coupling angle variability (CAV) has been introduced as a possible analysis method to quantify joint coordination variability. The purpose of this study was to assess the clinical usefulness of CAV measures from a dynamical systems perspective. This involved establishing the precision limits of CAV measures when physiological conditions are held constant, altering control parameters of knee pain and population then determining if the observed changes in CAV were clinically meaningful. 20 female recreational runners with PFP and 21 healthy controls performed a treadmill acclimation protocol then ran at a self-selected pace for 15 minutes. 3-D kinematics, force plate kinetics, knee pain and perceived exertion were recorded each minute. CAV were calculated for six knee-ankle combinations for 2 sets of 5 non-consecutive stride cycles at each capture period. Data were selected for the PFP group at a high (=>3) and low (<=high-2) pain level in a non-exhausted state (<14). Healthy data were used from the 11th minute of the running. Levels of agreement were performed between the 2 sets of CAV measures for both populations, a paired t-test compared low to high pain CAV measures and independent t-tests compared populations at the high pain state. Several CAV measures showed a significant increase in value with an increase in pain and were significantly greater for the PFP group. None of the observed changes exceeded the precision limits of all CAV measures investigated. These results do not agree with previous claims that less variability is indicative of pathology but rather the opposite. This suggests that there might be an optimal amount of variability to maintain a healthy coordinate state with deviations in any direction being detrimental. However; due to the volatile nature of CAV measures, the clinical use of CAV is not recommended using current analysis methods since changes observed weren’t considered clinically meaningful.
162

The Energy Expenditure of Heavy Metal Drummers

Brown, Joshua T. 01 July 2016 (has links)
The purpose of this investigation is to examine the energy demand of heavy metal drummers during rehearsal in order to understand the physiological responses. This information may lead to a better understanding of energy expenditure and add to the compendium of physical activity. The investigation consisted of eight apparently healthy 20 to 37-year-old males were recruited for this investigation. Information gathered during the drum test was average VO2, VO2peak, HR in beats per minute (bpm), metabolic equivalents (METs), and energy expenditure (EE) expressed in calories (kcals) per minute and per hour. Rating of perceived exertion (RPE) was used in addition to VO2 and HR values to assess physical demand. The Bruce Protocol maximal treadmill test was administered to compare the participants VO2max to their VO2peak while drumming. The EE during the 40-minute drum test was 387.05 + 83 kcals with an estimated hourly EE of 567.33 + 111.7 kcals. VO2, VO2peak, VE, and HR was 21.4 + 4.1 ml/kg/min, 33.9 + 8.1 ml/kg/min, 63.5 + 19 L/min, and 150.4 + 13.6 bpm respectively. The average MET level reached was six. RPE was 13.8 + 1.2 and is expressed as “somewhat hard” in difficulty according to the ACSM. Those categorized as having an average level of fitness reached 50-59% of their VO2max while the two individuals categorized as having an excellent level of fitness reached 42-45% of their VO2max. In conclusion, heavy metal drumming is a form of physical activity that is of moderate intensity and can be compared to other forms of recreational and work related physical activity.
163

Differences in Depression, Anxiety, and Life Satisfaction between Intercollegiate Athletes, Intramural Participants, and Non-Athletes

Wilson, Megan 01 October 2016 (has links)
It is widely supported that participation in athletics is positively correlated with increased overall health. However, some research indicates that participation in increased levels of competition is positively correlated with higher levels of depression and anxiety. This means, that if compared, athletes competing nationally or internationally would report higher levels of both depression and anxiety than athletes competing at the intercollegiate level. Research indicates that this could be caused by increased amounts of pressure, personal cost, and expectation. This study examines potential differences between intercollegiate, intramural, and non-athletes in these areas on a college campus. The first hypothesis is that depression symptoms will be more present in intercollegiate athletes than in intramural participants. The second hypothesis states that anxiety symptoms will be more prevalent in intercollegiate athletes than in intramural participants. The third hypothesis states that life satisfaction will be greater in intramural participants than in intercollegiate athletes. Lastly, the fourth hypothesis states that perceived social support and athletic identity will mediate the relationship between level of athletic participation and psychopathology. Participants in this study gave informed consent, completed a demographics questionnaire, and scales measuring depression and anxiety, life satisfaction, athletic identity, and perceived social support. The participants were recruited from intercollegiate teams, intramural teams, and psychology courses at Western Kentucky University. The first and second hypotheses were not supported since intramural participants did not have significantly different levels of depression compared to intercollegiate athletes and non-athletes. Results revealed intramural participants are more satisfied with life than intercollegiate and non-athletes, which supports the third hypothesis. The results also revealed that life satisfaction is mediated by both athletic identity and perceived social support, which shows partial support for the fourth hypothesis. The fourth hypothesis was not supported for depression and anxiety because these factors did not have significant differences between the groups so finding a mediating factor was not possible.
164

Lipid And Lipoprotein Metabolism In Response To Treadmill Walking At Two Levels Of Caloric Expenditure: A Comparison Of Black And White American Men

Kushnick, Michael R Unknown Date (has links)
The effect of acute exercise on blood lipids and lipoproteins has been examined and their response is believed to reflect the changes that occur as a result of chronic exercise training. The cross sectional differences between trained and untrained individuals and the results of longitudinal investigations suggest LDL particle size and distribution may be altered after acute exercise. Moreover, the response of the lipid and lipoprotein profile of Black men may be different than that of White men, owing to initial concentration differences or a genetic predisposition. PURPOSE: To examine the effects of expending 300 and 600 calories through treadmill walking at a moderate intensity (65% VO2max) on blood lipids and lipoproteins as compared to a non-exercise, control trial over the course of 72 hours. METHODS: Ten White and ten Black men participated in this study after being screened for strict inclusion criteria (including: parents/grandparents either Black or White and from the United States; sedentary, but otherwise healthy; VO2max 30-45ml⋅kg⋅min-1; and body fatness ¡Ü25%). Analysis of variance with repeated measures design was used (Group x Trial x Time). Blood was collected at Baseline (0hr), 12hr, 24hr, 48hr and 72hr for determination of blood lipid concentrations, LDL particle size, LDL distribution and CETPa. RESULTS: Black men of this investigation had higher HDL-C (49.4 vs 41.8 mg⋅dL-1), HDL3-C (35.1 vs 30.8 mg⋅dL-1) and CETPa (82.1 vs 52.8 pmol⋅ml-1⋅3hr-1) and lower TC (148.9 vs 177.1 mg⋅dL- 1), LDL-C (83.4 vs 116.3 mg⋅dL-1) and TC to HDL ratios (3.06 vs 4.46) than the White men (p<0.05) over the control period. There were no group differences detected in LDL particle size (White 25.63nm vs Black 25.79nm), LDL distribution (Zone 1, White 58.19% vs Black 64.71%; Zone 2, White 20.16% vs Black 16.31%; Zone 3, White 21.65% vs Black 18.98%), HDL2-C (White 11.5 vs Black 14.2 mg⋅dL-1), or TG (White 95.0 vs Black 79.4 mg⋅dL-1). Black and White men responded to acute exercise in similar fashion for these variables and therefore our statistical model collapsed the data into a single group by trial and over time. Exercise did not statistically alter TC, LDL-C, LDL particle size, LDL distribution, HDL2-C or CETPa in the 72 hours following each exercise bout. However, HDL-C was increased 6.2%, 10.1% and 5.8%, HDL3-C was increased 9.8%, 13.8% and 9.8%, while TG were reduced 24.8%, 27.3% and 22.4% at 12hr, 24hr and 48hr, respectively from the Base value of the 600 Kcal Trial. Additionally, TG were reduced 18.0% at 12hr from the baseline value of the 300 Kcal Trial. CONCLUSION: These results are the first to indicate that acute treadmill walking at moderate intensity of sufficient caloric expenditure modified HDL-C, HDL3-C and TG in Black men. No differences were determined in the manner in which Black and White American men statistically increased HDL-C and HDL3-C and reduced TG after acute exercise. In addition, there was no impact of acute exercise on TC, LDL-C, HDL2-C, CETPa, LDL particle size or LDL distribution in either group. However, these data suggest that Black/White differences exist in CETPa, where Black men have greater activity of this enzyme / Dissertation / PhD
165

Relationship Between Pectoralis Minor Length, Subacromial Space, and Pain in Swimmers and Overhead Athletes

Richards, Erika Jaci 01 August 2017 (has links)
Introduction (Context): The purpose of this study was to measure and correlate pectoralis minor length (PML) and acromiohumeral distance (AHD) in male and female collegiate swimmers, overhead athletes, and a control group. Methods: Participants underwent assessment of pain related to impingement syndrome with special tests (painful arc, external rotation resistance, empty can, and Neer's impingement test), as well as range of motion, measurement of PML, and measurement of subacromial space via ultrasound. Design: Cross-sectional, correlational study. Setting: University modalities laboratory. Participants: 60 healthy subjects (20 swimmers, 20 overhead athletes, 20 controls, age = 21.5 ± 2.4 years; height = 178.7 ± 10.2 cm; weight = 76.9 ± 13.4 kg; BMI = 24 ± 3.4) with 20 subjects in each of the 3 experimental groups: swimmers, overhead athletes, and control. Results: Height-normalized PML for both the dominant and nondominant arms was positively and weakly correlated with AHD at 0° (r = .361; p = .002; (r = .277; p = .016) respectively. Differences were shown between groups in AHD at 0° but no differences were shown in PML. Conclusions: There was a weak positive relationship between height-normalized PML and AHD at 0° both in dominant and nondominant shoulders. Swimmers and overhead athletes were observed to have more AHD than controls.
166

Gait Alterations and Plantar Pressure in Diabetic Peripheral Neuropathy: A Preliminary Study

Henderson, Adrienne Dora 01 July 2018 (has links)
Background: Despite a lack of consensus on its utility, clinicians have traditionally relied on plantar pressure (PP) to predict ulcer risk and prescribe interventions in individuals with diabetic peripheral neuropathy (DPN). Joint kinematics and kinetics have the potential to contribute to DPN assessment and treatment, however previous studies have not accounted for walking speed nor integrated a full-body analysis with a detailed foot model. Purpose: To assess PP and gait alterations in DPN by controlling walking speed and incorporating a multisegment foot model into a full-body gait analysis. We hypothesize that hip and ankle kinetics will be altered consistent with distal muscle weakness. Methods: Ten subjects with DPN (height: 178.79 ± 8.55 cm, weight: 108.78 ± 16.67 kg, age: 61.5 ± 13.53 years), and 10 healthy matched controls (height: 180 ± 6.37 cm, weight: 92.87 ± 14.5 kg, age: 59.4 ± 7.5 years) participated in this cross-sectional study. Fifty-six reflective markers were attached to each subject according to a full-body model, including a multisegment foot. Subjects walked at a controlled speed (1 m/s) while plantar pressure, kinematic and kinetic data were collected. Functional data analysis was used to compare kinematic and kinetic data between groups, while independent t-tests and a Benjamini-Hochburg procedure was used to compare plantar pressure and joint work metrics. Results: Individuals with DPN presented with a delayed transition from hip extension to hip flexion moment and a decrease in peak hip flexion moment. There were no major changes found at the knee. There was an increase in peak dorsiflexion angle and delayed power generation in both the ankle and midtarsal joints. DPN subjects also showed a decreased midtarsal positive work. The only significant PP metric found was a decrease in peak PP under the lateral toes. Conclusion: Findings demonstrated that individuals with DPN use a hip compensation mechanism to overcome distal muscle weakness. Ankle and midfoot alterations are consistent with muscle weakness, requiring proximal compensations. Joint mechanics were more informative than PP measurements and may provide additional insight into DPN assessment and treatment.
167

A Comparison of Linear and Daily Undulating Periodizied Strength Training Programs.

Caldwell, Andrew Morrow 18 December 2004 (has links)
The purpose of this study is to compare linear periodized (LP) and daily undulating (DUP) periodized strength training programs, and determine if either method of periodization elicits superior gains in 1 Repetitions maximums (1RM) for back squat (BS) and bench press (BP) (core exercises). Nineteen subjects (n=19) underwent a 6-week resistance-training (RT) program. Participants performed both BS and BP two day a week. The LP group linearly increased intensity while decreasing volume. While the DUP group daily changed intensity and volume. Total volume for both BS and BP were equal for both LP and DUP. Both BP and BS increased significantly from pre to post for both groups. However, there was no significant difference in pre-post strength measure in the LP compared to DUP.
168

Association Between Expanded Normal Weight Obesity and Insulin Resistance Among U.S. Adults in the National Health and Nutrition Examination Survey

Martinez, Keilah Elizabeth 01 June 2016 (has links)
The purpose of this investigation was to expand the evaluation of Normal Weight Obesity (NWO) and its association with insulin resistance using a nationally representative sample of U.S. adults. A cross-sectional study including 5,983 subjects was conducted. Body fat percentage was assessed using dual energy X-ray absorptiometry (DXA). Expanded Normal Weight Obesity (eNWO) categories (pairings of BMI and body fat percentage classifications) were determined by standard cut-points for BMI and the gender specific median for body fat percentage. Homeostatic Model Assessment-Insulin Resistance (HOMA-IR) levels were used to index insulin resistance. Mean ± SE values were as follows: BMI: 27.9 ± 0.2 (women) and 27.8 ± 0.1 (men); body fat percentage: 40.5 ± 0.2 (women) and 27.8 ± 0.2 (men); HOMA-IR: 2.04 ± 0.05 (women) 2.47 ± 0.09 (men). HOMA-IR differed systematically and in a dose-response fashion across all levels of the eNWO categories (F = 291.3, P < 0.0001). As BMI levels increased, HOMA-IR increased significantly and within each BMI category, higher levels of body fat were associated significantly with higher levels of HOMA-IR. Both high BMI and high body fat percentage are strongly related to insulin resistance. In this study, insulin resistance increased incrementally according to BMI levels primarily and body fat levels secondarily. Consequently, due to the costs associated with precisely measuring body fat, and the accuracy of using BMI independently, we recommend that BMI be used in its standard form to predict insulin resistance and not be supplemented with an estimate of body fat.
169

The Effects of Experimental Anterior Knee Pain on Bilateral Ground Reaction Forces During Running

Cronk, Emily Rachel 01 December 2016 (has links)
The purpose of this study was to examine the independent effects of anterior knee pain (AKP) on bilateral ground reaction force (GRF) during running, with a focus on GRF applied to the uninvolved leg, which, prior to this study, had never been evaluated. Twelve volunteers completed three data collection sessions, that corresponded to one of three conditions (control, sham, and pain), in a counterbalanced order. For each session, subjects ran for five minutes. For the pain and sham sessions, respectively, hypertonic and isotonic saline were infused into the infrapatellar fat pad of the right leg during the running, while no infusion was involved in the control session. GRF data were collected during the final 30 seconds of running. Functional statistics were used to determine the effects of session and leg (right and left) on vertical and anterior-posterior GRF throughout the stance phase of running. A mixed model ANOVA was used to determine the effect of session and leg on vertical GRF load rate, impulse due to vertical, propulsive, and braking GRFs. A repeated measures ANOVA was used to determine the effect of session and time on subject-perceived pain. Alpha was set to 0.05 for all statistical comparisons. Unexpectedly, no significant session × leg interaction existed for vertical GRF at any time point during stance phase of running. Similarly, the experimental AKP did not affect impulse due to vertical GRF or load rate for the vertical GRF. There was, however, a significant session × leg interaction for anterior-posterior GRF. For the pain session, involved-leg braking GRF was 11% greater than uninvolved-leg braking GRF, during the first 9% of stance phase. There was also a significant between-session difference for involved-leg braking impulse (p = 0.023) and uninvolved-leg propulsive impulse (p = 0.027). The mean involved-leg braking impulses were 11.3 Ns (± 0.6), 13.2 Ns (± 0.6) and 13.2 Ns (± 0.6) for the pain, control, and sham sessions, respectively. Mean uninvolved-leg propulsive impulses were 14.8 Ns (± 1.3), 13.6 Ns (± 1.3), and 13.5 Ns (± 1.3) for the pain, control, and sham sessions, respectively. These differences in anterior-posterior GRF might reflect a compensatory unloading of the involved leg due to AKP.
170

Lower Extremity Neuromechanics During a Forward-Side Jump Following Functional Fatigue in Patients with Ankle Instability

Kim, Hyun 01 June 2015 (has links)
Ankle instability (AI) and fatigue impair neuromuscular control as well as dynamic joint stability of the lower extremity. No one has comprehensively examined the effects of AI and fatigue on neuromechanics of the lower extremity during a functional activity. Deficits associated with AI and fatigue could be additive in increasing the risk for injury in patients with AI. PURPOSE: To examine the interaction of AI and fatigue on lower extremity muscle activity, kinematic, and kinetic patterns during a forward-side jump. METHODS: 25 AI (23.3 ± 1.9 yrs, 176.5 ± 10.5 cm, 70.9 ± 11.4 kg), and 25 matched control subjects (23.7 ± 2.5 yrs, 175.0 ± 10.8 cm, 70.3 ± 12.8 kg) were categorized according to the Foot and Ankle Ability Measure (FAAM) (ADL: 84.3 ± 7.6%, Sport: 63.6 ± 8.6%) and the Modified Ankle Instability Instrument (MAII) (3.7 ± 1.2). Fifty-nine reflective markers were place over anatomical landmarks and eight electromyography (EMG) electrodes were placed on tibialis anterior (TA), peroneus longus (PL), medial gastrocmedius (MG), medial hamstring (MH), vastus lateralis (VL), adductor longus (AL), gluteus medius (GMed), and gluteus maximus (GMax) muscles in the involved leg. Subjects performed five forward-side jumps on a force plate before and after functional fatiguing exercises. To induce fatigue, subjects began 5-min incremental running on a treadmill between 5 and 6 mph. Next, subjects performed 20-second lateral counter movement jumps (CMJ), and 20 vertical CMJs. After each fatigue cycle, subjects performed one max vertical jump. Subjects repeated three exercises until Borg's rating of perceived exertion (RPE) reached 17 and the vertical jump height fell below 80% of their max jump height. Functional analysis of variance (FANOVA) (p < 0.05) was used to evaluate differences (a group by fatigue interaction) between two conditions (pre- vs post-fatigue) in each group (AI and control) for lower-extremity kinematic, kinetic and neuromuscular patterns. Pairwise comparison functions as well as 95% confidence interval (CI) bands were plotted to determine specific differences. If 95% CI bands did not cross the zero line, we considered the difference significant. RESULTS: Compared to the control group, the AI group demonstrated less range of dorsiflexion, knee and hip flexion motions during early phase of landing after fatigue. For sagittal-plane hip kinetics, subjects with AI decreased the hip extension moment while control subjects increased hip extension moments during landing following functional fatiguing exercise. The AI group showed less reduction of anterior-posterior ground reaction force (AP GRF) during transition phase of a forward-side jump after fatigue compared to control subjects. The AI group decreased EMG amplitude of PL, MH, and GMed while increased VL and GMax during landing after fatigue compared to control subjects. CONCLUSION: AI subjects demonstrated greater impairments in neuromechanical control patterns than a matched control group during a sport movement as fatigue progressed. Compared to AI group, control subjects showed a coordinated joint control strategy after fatigue, increasing joint angles from distal (ankle) to proximal (hip) joints by increasing hip extensor moments during landing from a forward-side jump in an attempt to reduce ground impact force. EMG alterations were consistent with patterns observed in injured patients, which may predispose patients to poor positions associated with lower extremity joint injury. These interactions between neuromuscular fatigue and AI may predispose individuals to lower extremity injuries.

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