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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.
91

A pilot study to examine a therapeutic exercise intervention on fibromyalgia symptoms

Nelson, Mara Hendricks 21 March 2006 (has links) (PDF)
Objective. To examine the feasibility of a home-based, video therapeutic exercise program on pain, fatigue, self-efficacy, and health status in fibromyalgia patients. Methods. Nine individuals who were previously diagnosed with fibromyalgia completed the study (out of an initial pool of 31). Subjects were randomly assigned to one of two groups: a group who received a home-based therapeutic exercise video and a control group who continued to undergo their current standard of care or "treatment-as-usual." The video group was instructed to conduct the exercises as prescribed in the 42-minute video at least 3 times per week for 4 weeks. The treatment-as-usual control group was instructed to continue to undergo their current standard-of-care and to not begin any new treatments during that time. Instruments measuring self-efficacy, pain, fatigue, self-rated health status and health distress were administered at baseline and 4 weeks. Results. None of the variables analyzed showed a significant change between the treatment and control groups over the course of the 4-week study. Conclusion. This study was not sufficiently powered to detect differences between the two groups. However, several of the treatment group participants subjectively indicated that they found the exercises to be helpful in the management of their fibromyalgia symptoms and the program did not exacerbate any of their symptoms. With this information, it appears that patients are able to tolerate the treatment and are able to complete the outcome measures. Between-group clinical outcomes will now need to be assessed in a larger clinical trial.
92

Whole-Body Vibration and Its Effects on Electromechanical Delay and Vertical Jump Performance

Stevenson, Deja Lee 27 June 2005 (has links) (PDF)
The purpose of this study was to determine the effects of whole-body vibration on electromechanical delay and vertical jump performance. Twenty college aged subjects participated in 10 intervals of whole-body vibration (WBV) at a frequency of 26 Hz and amplitude of 5 mm. Each interval consisted of 60 s of WBV in a half-squat followed by 60 s of rest. After 5 intervals, subjects had 6 min of rest before the final 5 intervals. Each subject also participated in the control which included the same 10 intervals in a half-squat without the WBV. Tests were conducted to assess electromechanical delay (EMD) and vertical jump at baseline, during the 6 min rest period and immediately after the treatment and control. EMD was measured using tibial nerve stimulation and a force plate. EMD was recorded as the lag time between the initiation of gastrocnemeus stimulation and plantar flexion force production. Vertical jump was measured using a force plate and subjects' flight time. The factorial ANOVA results showed no differences between groups, the control and WBV treatment, for both EMD (F (2, 38) = 1.385, p = 0.263) and vertical jump (F (2, 38) = 0.040, p < 0.96). The WBV treatment protocol chosen had no effect on vertical jump. These results suggest that WBV, using this protocol, is not effective for acute vertical jump or EMD enhancement. Also, since there was no effect on EMD, this suggests that the WBV treatment did not enhance muscle spindle sensitivity.
93

The Effects of Low Frequency Ultrasound in Transdermal Drug Delivery

Wells, Aaron M. 09 July 2010 (has links) (PDF)
Objective: Determine if varying ultrasound frequency affects the delivery of 10% hydrocortisone concentrations during phonophoresis. Utilize intramuscular microdialysis probe for drug collection, thus improving the experimental model. Methods: Thirty one (10 in groups 1 and 2, 11 in group 3) healthy subjects participated in this study. Interventions: Subjects were randomly assigned to one of three treatment groups receiving 10 minute ultrasound treatments applied to a standardized area of the gastrocnemius muscle of the right leg. The ultrasound was performed over the treated area using a 10% hydrocortisone compound mixed with standard ultrasound gel. The contralateral limb served as the control (no mixed compound or treatment) for all groups. Group one received sham ultrasound. Medicated gel was placed on the treatment site, the sound head moved, but no ultrasound was applied. Group two received 45 KHz at .056 w/cm2. Group three received 1 MHz at 1.0 w/cm2 at a 50 % duty cycle. Results: There was no difference in cortisol concentration change during treatment between the three treatment groups on the treated limbs (sham = 1.1 ±7.5 ng/ml, 45 KHz = 1.1 ± 1.5 ng/ml, 1 MHz = 4.1 ± 7.8 ng/ml; F2,22 = .34, P = .72) or control limbs (sham = 1.65 ± 6.6 ng/ml, 45 KHz = -1.3 ± 2.7 ng/ml, 1 MHz = 0.37 ± 8.1 ng/ml; F2,22 = .67, P = .546). No difference was found in cortisol concentration change during treatment between the treatment limbs and the control limbs (treatment = 2.1 ± 6.2 ng/ml, control = 0.20 ± 5.9 ng/ml; F1,22 = .9, P = .35). The following factors were found to influence cortisol concentrations levels in dialysate collected during treatment: depth of muscle in the treatment limbs (F1,22 = 6.4, P = .02), microdialysis probe depth in the control limbs (F1,22 = 4.1, P = .05), and pre treatment cortisol level in the control limbs (F1,22 = 10.1, P = .004. Conclusions: There was no evidence altering ultrasound frequency from 45 KHz to 1 MHZ enhanced the delivery of 10% hydrocortisone to treatment tissues under these experimental conditions.
94

Kinematic Changes of the Tennis Forehand Ground Stroke as Post Contact Ball Speed Increases

Funk, Merrill D. 04 November 2010 (has links) (PDF)
Neuromuscular and kinematic patterns during the tennis forehand have been studied extensively. However, no one has evaluated potential upper-extremity kinematic changes during the forehand as ball speed increases. The purpose of this study was to evaluate changes in shoulder and trunk kinematics as forehand ball speed increased, in an attempt to better understand how kinematics may promote forehand ball speed. Peak trunk rotation angle, shoulder horizontal abduction/adduction and internal/external rotation angle, and corresponding angular velocities were measured between initial backswing and ball contact during forehands that were performed at three different speeds (50%, 75%, and 100% of maximal post-impact ball speed). Between-speed differences were observed for all dependent variables. Internal humeral rotation velocity increased by 136% (from 477°/s to 1128°/s) while trunk rotation velocity increased by 91% (from 164°/s to 313°/s) and trunk rotation angle increased by only 26% (from 46° to 58°) as forehand ball speed increased from slow to fast. Two primary conclusions can be drawn from these results: (1) trunk and upper arm rotation (adduction and internal rotation) are important to produce forehand ball speed, and (2), increased joint angular velocity may be more important than altered joint position when attempting to produce maximal forehand ball speed.
95

The Pre-Application of Hydrocortisone Cream and Its Effect on Transdermal Drug Delivery by Phonophoresis

Webb, Patrick Thomas 13 December 2012 (has links) (PDF)
Context: Transdermal delivery of hydrocortisone by phonophoresis is used for the treatment of musculoskeletal conditions. Research shows hydrocortisone and other white or opaque topical preparations transmit ultrasound energy poorly. Effective transmission of ultrasound is important in phonophoresis. Main Outcome measured: Samples of subcutaneous interstitial fluid were collected during and for 20 minutes following phonophoresis treatment. Cortisol concentrations were analyzed by an enzyme linked immune-assay (ELISA) test. Objective: Determine the subcutaneous cortisol concentration after two different phonophoresis treatments using a 2.5% hydrocortisone preparation. Design: Randomized design in which 22 healthy participants were assigned to receive a phonophoresis treatment where: 1) hydrocortisone cream was rubbed in completely prior to phonophoresis or 2) hydrocortisone powder was compounded with an ultrasound coupling gel. Test Subjects: 22 healthy individuals were recruited: 13 females with a mean age of 21 years and 9 males with a mean age of 21.8 years. Intervention: Phonophoresis consisted of pulsed ultrasound at 1 MHz, 1.0 w/cm2, and a 50% duty cycle. The treatment duration was 10 minutes and was localized over the distal gastrocnemius muscle. Results: We observed no significant difference in subcutaneous cortisol concentration between the two phonophoresis treatments (p=0.05). Also no significant difference was detected between pre and post-treatment cortisol levels within each individual treatment group. Conclusions: Our data indicates that completely rubbing a topical hydrocortisone application into the skin prior to placement of ultrasound gel does not result in increased transdermal delivery of cortisol when compared with the use of a compound of ultrasound gel and hydrocortisone powder applied topically to the skin.
96

Ultrasound Measured Flexor Muscle Thickness in the Forearms of Rock Climbers

Marsala, Michael 01 January 2019 (has links)
PURPOSE: To examine differences in the forearms of rock climbers using ultrasound to measure the muscle thickness of the finger flexors. METHODS: A total of 33 participants were recruited, 22 climbers (22.23 years; 68% male) and 11 controls (21.8; 55% male). Climbers provided self-reported ratings of their climbing ability, skill level, and preferred mode of climbing (e.g. sport climbing vs. bouldering). Anthropometric measures, including body fat percentage, were measured in all participants. Ultrasound measurements were taken with the participant lying on their back on a padded table with their dominant hand supinated. Muscle thickness measurements were taken at the forearm where a peak of the forearm flexors was identified on the medial aspect of the forearm after a circumference measurement and small mark was made. The distance from the ulna and radius to the muscle-skin interface was measured, as well as echo intensity surrounding the median nerve using a third party program. RESULTS: Approximately 50% of climbers rated themselves as "intermediate", and the other 50% rated themselves as "advanced" climbers, while 77% of the 22 climbers classified themselves as primarily "sport climbers", and 23% classified themselves as "boulderers". Body fat percentages were significantly different at 19.14±6.99 and 30.02±7.6 for climbers and controls. Ulnar and radial muscle thickness values were significantly higher in climbers, 4.23±.39and 2.32±.39, respectively, and 3.61±.6 and 1.84±.31 in controls (p < .001). No differences in echo intensity were observed between climbers and non-climbers. DISCUSSION: The findings suggests that there are differences in flexor muscle thickness observed in earlier stages of rock climbing. Echo intensity of the flexor muscles were also measured, however significant variance in results warrants further investigation. Future studies should consider larger samples to better determine differences among muscle thickness and echo intensity across climbing abilities and mode of climbing, thus allowing for more specific training programs to be developed at each phase of training.
97

Accuracy of Commercial Fitness Trackers During High-Intensity Functional Training

Wessel, Paige 01 July 2016 (has links)
Commercially available fitness trackers have been found to accurately measure steps and caloric expenditure during walking and running activities. Circuit-style, highintensity functional training (HIFT) has become increasingly popular because it is inexpensive and effective in improving muscular strength and cardiovascular fitness. PURPOSE: To evaluate the accuracy of five accelerometers (ActiGraph GT3X, Nike Fuelband, Fitbit One, Fitbit Charge HR, and Jawbone UP Move) in estimating energy expenditure while performing an acute bout of HIFT. METHODS: Participants (n = 47) underwent baseline testing and at least 48 hours later, each participant completed the main test: a 15-minute workout consisting of 12 repetitions each of 7 different exercises; performed circuit-style by completing as many rounds as possible. During the main test, each participant wore the Cosmed K4b2 portable metabolic analyzer (PMA) and five different accelerometers. RESULTS: Four of the five fitness trackers reported lower (p <0.01) total caloric expenditure values compared to the PMA during the acute bout of HIFT. The waist-mounted device (ActiGraph, 182.55 ± 37.93 kcals) most closely mimicked caloric expenditure compared to the PMA (Cosmed, 144.99 ± 37.13 kcals) as indicated by an insignificant p value (0.056). Systematic differences between the activity monitors were calculated using an Intraclass Correlation (ICC) with an ICC = -0.032. The ICC of F (46,235) = 0.812 (p = 0.799) was not significant at the predetermined 0.05 alpha level. A Repeated Measures ANOVA showed that when compared to the Cosmed, all activity monitors were significantly different at the 0.05 alpha level. The Fitbit One and the Fitbit Charge HR were the only two activity monitors that are not significantly different from one another (p = 0.985). The range of error based on mean absolute percentage errors (MAPE) was lowest for the ActiGraph (15.1%) and highest for the Fitbit Charge HR (22.1%). CONCLUSION: The wrist- and hip-mounted fitness trackers do not accurately assess energy expenditure during HIFT exercise. Supported by: WKU Graduate School, NIGMS 2P20 GM103436-14; Institutional Development Award (IDeA) from National Institute of General Medical Sciences, National Institutes of Health, 5P20GM103436 and the WKU RCAP Grant 14-8007.
98

A Non-Exercise Based Estimation of the Critical Running Velocity and Anaerobic Running Capacity in Competitive Runners

Switalla, Jonathan R. 01 January 2016 (has links)
This study examined: 1) if estimated performance times (ETcom) at four different distances can be used to accurately define the parameters of the critical velocity (CV) test [CV and anaerobic running capacity (ARC)]; and 2) if those parameters can be used to predict time to completion (PTcom) of distances performed at velocities greater than CV. Twelve subjects provided an ETcom for maximal-effort runs at 400m, 800m, 1600m, and 3200m. The CV and ARC were derived from the total distance (TD) versus ETcom relationship. The equation: PTcom = ARC / (velocity-CV) was used to determine the PTcom for runs at 200m, 600m, and 1000m. The PTcom was validated against the actual time to complete (ATcom) runs at the same three distances. The TD versus ETcom relationship was highly linear and indicated a close relationship between running distance and time. The PTcom overestimated the ATcom at 200m, but was not different from ATcom at 600m and 1000m. The PTcom and ATcom were not related at any of the three distances. The CV model could be applied to estimated performance times to derive the CV and ARC parameters, but the parameters of the test did not accurately estimate performance times above CV.
99

The role of psychological characteristics of developing excellence (PCDEs) in negotiating the pathway to excellence

Macnamara, Aine January 2010 (has links)
The development of talent is a complex process mediated by a host of psychology, social, physical, and environmental variables. Unfortunately, the multiple processes involved in talent development (Gagne, 2004; Simonton, 2001) are frequently ignored by the systems and protocols employed in sport. Modem approaches to talent development are beginning to stress the initial possession, then subsequent development, of Psychological Characteristics of Developing Excellence (PCDEs; MacNamara, Button, & Collins, 2010) as the best way to realize latent potential. Accordingly, the aim of this thesis was to acknowledge this complexity by identifying the psycho-behavioural factors that co-act with physical potential and practice regimes to enhance the efficacy of TID models in sport. The main objectives of this thesis were: 1. To identify the challenges faced along the pathway to excellence and the PCDEs that facilitate the successful negotiation of the pathway to excellence across different performance domains. 2. To identify whether PCDEs are operationalised differentially depending, on an individual's age, stage, and context. 3. To confirm these differential roles through quasi-longitudinal examinations of longterm employment (in musicians) and across a key transition (in athletics, the transitions to university at 18 years of age). 4. To develop a questionnaire to bridge the theory-practice divide in TO processes and enable formative evaluation of PCDEs by practitioners. 5. To provide preliminary validation of the questionnaire by evaluating its discriminant function between good and poor development athletes. The development of talent is a complex process mediated by a host of psychology, social, physical, and environmental variables. Unfortunately, the multiple processes involved in talent development (Gagne, 2004; Simonton, 2001) are frequently ignored by the systems and protocols employed in sport. Modem approaches to talent development are beginning to stress the initial possession, then subsequent development, of Psychological Characteristics of Developing Excellence (PCDEs; MacNamara, Button, & Collins, 2010) as the best way to realize latent potential. Accordingly, the aim of this thesis was to acknowledge this complexity by identifying the psycho-behavioural factors that co-act with physical potential and practice regimes to enhance the efficacy of TID models in sport. The main objectives of this thesis were: 1. To identify the challenges faced along the pathway to excellence and the PCDEs that facilitate the successful negotiation of the pathway to excellence across different performance domains. 2. To identify whether PCDEs are operationalised differentially depending, on an individual's age, stage, and context. 3. To confirm these differential roles through quasi-longitudinal examinations of longterm employment (in musicians) and across a key transition (in athletics, the transitions to university at 18 years of age). 4. To develop a questionnaire to bridge the theory-practice divide in TO processes and enable formative evaluation of PCDEs by practitioners. 5. To provide preliminary validation of the questionnaire by evaluating its discriminant function between good and poor development athletes. The development of talent is a complex process mediated by a host of psychology, social, physical, and environmental variables. Unfortunately, the multiple processes involved in talent development (Gagne, 2004; Simonton, 2001) are frequently ignored by the systems and protocols employed in sport. Modem approaches to talent development are beginning to stress the initial possession, then subsequent development, of Psychological Characteristics of Developing Excellence (PCDEs; MacNamara, Button, & Collins, 2010) as the best way to realize latent potential. Accordingly, the aim of this thesis was to acknowledge this complexity by identifying the psycho-behavioural factors that co-act with physical potential and practice regimes to enhance the efficacy of TID models in sport. The main objectives of this thesis were: 1. To identify the challenges faced along the pathway to excellence and the PCDEs that facilitate the successful negotiation of the pathway to excellence across different performance domains. 2. To identify whether PCDEs are operationalised differentially depending, on an individual's age, stage, and context. 3. To confirm these differential roles through quasi-longitudinal examinations of longterm employment (in musicians) and across a key transition (in athletics, the transitions to university at 18 years of age). 4. To develop a questionnaire to bridge the theory-practice divide in TO processes and enable formative evaluation of PCDEs by practitioners. 5. To provide preliminary validation of the questionnaire by evaluating its discriminant function between good and poor development athletes. To address the first and second objective, Chapter 3 describes a retrospective, qualitative study of the careers of elite performers. The findings of this study suggest that the pathway to excellence is complicated by the specific challenges faced within different performance domains. However, a similar set of PCDEs, albeit differentially deployed, were reported by all participants as facilitators of development. Chapters 4 and 5 employed a quasi-longitudinal research design to address Objective 3 - the differential deployment of PCDEs in particular contexts. Using a sliding populations methodology, young classical musicians were tracked over a 2-year period to explore the PCDEs employed during the macro and micro stages they encountered as they progressed. A similar research design was employed in Chapter 4 to examine the use of PCDEs during a critical transitional period for track and field athletes. Although the results point to the generality of PCDEs at both elite and developmental levels, and across performance domains, there appeared to be an understandable and necessary shift in responsibility from significant others promoting and reinforcing PCDEs in the early years towards self-initiated and autonomous behaviours in the later years; in essence, a shift in the source of regulation (Cleary & Zimmerman, 2001). The studies in Chapters 3, 4, and 5 generated a list of PCDEs that facilitated development, along with an understanding of how PCDEs were deployed differentially along the pathway to excellence. These findings were used to develop the Psychological Characteristics of Developing Excellence Questionnaire (PCDEQ); a questionnaire designed to assess the possession and strategic deployment of the PCDEs. Chapter 6 reported the systematic generation of questionnaire items and an exploratory factor analysis that resulted in a 59- item, 6 factor stnicture PCDEQ. The PCDEQ displayed good psychometric properties and should provide coaches with a theoretically and empirically supported tool to assess, monitor, and develop these key developmental skills. To address the final objective, Chapter 7 presents a discriminant function analysis which revealed that the PCDEQ had very good discriminant function and was able to classify between 67 per cent and 75 per cent of athletes correctly on the basis of their self-reported behaviour in sport. In conclusion, the studies reported in this thesis provide a significant contribution to current knowledge by shifting the fopus away from TID methods based on prediction and correlation towards a consideration of progress and behaviour during development. Future recommendations include the need for further validation of the PCDEQ as well as longitudinal and action-based research assessing the role of PCDEs in talent development.
100

Passive Hallux Adduction Decreases Blood Flow to Plantar Fascia

Dunbar, Julia Lorene 01 July 2018 (has links)
Purpose: Due to the vital role that blood flow plays in maintaining tissue health, compromised blood flow can prevent effective tissue healing. An adducted hallux, as often seen inside a narrow shoe, may put passive tension on the abductor hallucis, consequently compressing the lateral plantar artery (LPA) into the calcaneus and thus restricting blood flow. The purpose of this study was to compare blood flow within the LPA before and after passive hallux adduction (PHA). Methods: Forty-five healthy volunteers (20 female, 25 male; age = 24.8 ± 6.8 yr; height = 1.7 ± 0.1 m; weight = 73.4 ± 13.5 kg) participated in this study. Blood velocity and vessel diameter measurements were obtained using ultrasound imaging (L8-18i transducer, GE Logiq S8). The LPA was imaged deep to abductor hallucis for 120 seconds: 60 seconds at rest followed by 60 seconds of PHA. Maximal PHA was performed by applying pressure to the medial side of the proximal phalanx of the hallux. Blood flow was then calculated in mL/min, and pre-PHA blood flow was compared to blood flow during PHA. Results: Log transformed data was used to run a paired t-test between the preadduction and postadduction blood flow. The volume of blood flow was 22.2% lower after PHA compared to before (–0.250 ± 0.063, p < 0.001). Conclusion: Although PHA is only a simulation of what would happen to the hallux inside of a narrow shoe, our preliminary findings of decreased blood flow through PHA suggest blood flow in narrow footwear and its effects on tissues within the foot are worth investigating.

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