Physical inactivity is one of the major public health problems in many parts of the World. In Scotland it is reported that two thirds of Scottish adults (>16yrs) and one third of Scottish children (<16yrs) do not do sufficient physical activity to gain the health benefits of physical activity. Furthermore, there is still much debate about the nature and volume of physical activity required to provide health benefits. Therefore, more investigations are required to help improve our understanding of the links between physical activity, obesity and health. In addition, the assessment of habitual physical activity needs to be accurately quantified using appropriate methods that are valid and reliable. The main aims of this thesis were thus to assess the validity and reliability of three new generations of movement sensing devices (Actigraph, ActivPAL and SenseWear PRO2) in adults and adolescents in a controlled laboratory environment and to then use the most valid and reliable device in assessing the habitual physical activity of adults (lean and overweigh/obese) and adolescents in a free-living situation. Following objectively assessing the habitual physical activity, investigation of the associations between physical activity status and cardiovascular and metabolic disease risk markers in adults and adolescents were the last main aims of this thesis. In the first study, the results indicated that the new generations of the three devices were reliable in assessing EE during walking on the flat and on a 5% incline in lean and overweight/obese adults and lean adolescents. However, none iii of these devices and the methods or programme versions that were selected and applied was able to accurately estimate EE during walking on a treadmill. However, based on the sensitivity data obtained and previous evidence, the Actigraph was considered the most appropriate device for assessing the habitual physical activity due to its ability to discriminate between physical activity intensities. The second and third studies concluded that adults (including lean and overweight/obese) met the recommended physical activity guidelines for health and wellbeing purposes. However, the data suggest that overweight/obese participants may need to be advised to spend more time in MVPA and probably more vigorous activity to not only reduce body fat but also to increase cardiorespiratory fitness and reduce their chances of future cardiovascular and metabolic disease. The fourth and fifth studies, demonstrated that the Scottish adolescents –in the cross sectional study- were below the recommended physical activity guidelines. When the method of physical activity assessment was adjusted the Scottish adolescents were similar to the adolescents in other European countries and were observed to be more active than adolescents in some of the developed countries such as American adolescents (Texas State). In the case of lean adolescents who have a low physical activity- but who are not sedentary- the cardiovascular and metabolic disease risk markers may not be obvious at this stage, but the differences in glucose and HOMA-IR suggest that there may be early signs of progression towards metabolic disease in this group. iv The importance of the associations between vigorous physical activity and body fat, as well as between body fat and the risk markers of metabolic disease, suggests that future intervention studies should focus on monitoring the outcome from vigorous physical activity interventions vs. moderate activity within current guidelines.

Wheelchair-bound paraplegics are in an unnatural, almost all-day sitting position. This is physiologically disadvantageous as it may cause increased abdominal pressure, renal dysfunction, pressure sores, muscle atrophy and osteoporosis. Thus it would be beneficial, physiologically and psychologically, for a paraplegic to be able to stand for temporary periods of time. As a result of the muscle atrophy and functional degeneration that follows a spinal cord injury, it is essential for paraplegics to undergo a muscle restrengthening program, using Functional Neuromuscular Stimulation (FNS), before standing up under FNS control can be attempted. Six healthy spinal cord injured subjects with spinal lesions between CS and T9 (two tetraplegics and four paraplegics) exercised their quadriceps muscles at home using a portable two-channel FNS muscle stimulator. The muscles were exercised against an increasing load to maximise the training effect. Inclined standing exercise, under FNS control, was performed in the Inclistand. The subjects' general state of health and fitness were assessed, namely their responses during a maximal arm ergometry exercise test, arm muscle function, lung function, blood biochemistry and their dietary habits. Subjects have shown improvement in quadriceps muscle strength, fatigue resistance and muscle bulk to varying degrees - according to their individual circumstances. The tetraplegics responded in a different manner to that of the paraplegics. The muscle strength increased significantly by a mean (+SD) of 97,8 + 59,6% and 171,2 + 118,1% for the four paraplegics, left and right leg respectively. There was a mean improvement of 16% in fatigue resistance in the left leg (p=0,08), while the mean response of the right leg varied. Quadriceps muscle bulk increased by 4,43 + 3,4% (left) and 2,7 + 2,1% (right) (0,05&lt;p&lt;0,l). The amount of subcutaneous fat around the mid-thigh decreased significantly by 4,73 + 1,4% (left) and 3,43 + 1,1% (right leg). The group was in a state of general well-being, with the exception of one subject whose serum cholesterol concentration fell within the high risk category. This study therefore showed that the FNS was sucessful in improving the quadriceps muscle strength, bulk and fatigue response of the SCI people in our research group. The valuable experience gained from this FNS study will be used to improve the present program.

No description available.

Dissertation submitted in partial compliance with the requirements for the Master’s degree in technology: Chiropractic, Durban University of Technology, Durban, South Africa, 2013. / Background: Forward head posture (FHP) is a common postural abnormality that is commonly associated with weak deep cervical flexor muscles (DCF). The craniovertebral (CV) angle lies between a horizontal line running through C7 spinous process and a line connecting the C7 spinous process to the tragus of the ear. The smaller the angle, the greater the forward head posture. Weak DCF musculature and FHP has been linked to cervical dysfunction in the short and long term such as cervicogenic headache and premature development of cervical regional degenerative joint disease. Improving isometric endurance and neuromotor control of the DCF muscles using craniocervical flexion exercise (CCFE) has been shown to be efficient in patients experiencing cervical dysfunction such as headache, although the relevance of CCFE has not been established in the asymptomatic group. Deficiency in the activity of these muscles can be accurately measured using craniocervical flexion testing (CCFT). There is a paucity of information regarding the definitive relationship between weakness of the DCF and FHP in asymptomatic participants. This research will help establish an efficient and safe prophylactic treatment protocol preventing long term sequela associated with FHP. Objectives: To determine the effect of CCFE on cervical posture by assessment of the CV angle in asymptomatic participants as well as to determine the effect of CCFE on cervical range of motion by assessment of flexion, extension, bilateral rotation and lateral flexion movements in asymptomatic participants whilst measuring the effect of CCFE on isometric endurance and neuromotor control of the DCF muscles assessed by the CCFT in asymptomatic participants. Method: This is a quantitative pre/post intervention study comparing the results of one group of 45 asymptomatic participants before and after the CCFE protocol has been allocated to them over a period of 3-5 weeks. Participants FHP was assessed by measuring the CV angle. This was done by marking the C7 spinous process and extending a horizontal line toward the shoulder. Then marking the tragus of the ipsilateral ear and measuring the angle using the smart tool angle finder (MD products). iv CCFT measurements were taken and the CCFE protocol allocated to those who qualified to take part in the study. Lastly, cervical range of motion was measured. This group received a home exercise protocol of 3 sets of 10 supine chin tucks daily with each repetition being held for 10 seconds. The technique was first ensured by the researcher prior to leaving the consultation rooms and an exercise diary was given to the participant until the 5th and final consultation to record the progress and efficiency of the home programme as well as any complaints regarding this. Result: The asymptomatic group included in the study improved in both the seated and standing CV angle measurements in that the CV was greater at the conclusion of the pre/post intervention (p=0.00000002) and (p=0.000003) respectively . Cervical range of motion showed improvement in some but not all ranges. Flexion showed a reduction in range of motion (p=0.0086) which was significant. Extension showed an improvement in range of motion (p=0.0000002) which was significant. Rotation toward the left (p=0.00003) and right (p=0.00063) showed an improvement in range of motion which was significant. Lateral flexion showed improvement which was not significant in both, left (p=0.0145) and right (p= 0.24985) ranges of motion. Neuromotor control showed 100 percent improvement in that all 45 of the participants were able to perform CCFT correctly through all five stages at conclusion of the study. Conclusion: Therefore it can be concluded that asymptomatic participants will benefit from CCFEs In terms of CV angle improvement, cervical range of motion as well as neuromotor control of the DCF muscles.

Dissertation submitted in partial compliance with the requirements for the Master’s Degree in Technology: Chiropractic at the Durban University of Technology, 2009 / Objectives: When we consider the body position of a field hockey player, the lumbar spine is always in a flexed position, which combined with rotational movements during various hitting and pushing techniques, increases the strain upon the spine and surrounding muscles, thus leading to low back pain. To determine the relationship between core strength and trunk extensor endurance relating to the incidence of acute low back pain in field hockey players. Project Design: The research project was in the form of a quantitative cross-sectional study, using human subjects. Setting: The research project occurred during the field hockey season (2008) with players who had acute low back pain. The players were clinically assessed and subdivided into necessary groups at the Chiropractic Day Clinic at the Durban Institute of Technology. Subjects: Adult, male patients, aged between 18 and 30 years of age, playing premier field hockey. Out of the thirty players, 12 players have played in the National u/21 squad, 7 players have played in a Junior National team and 11 players have played senior provincial field hockey. Outcome measure: This included three tests. Firstly, the absolute difference of pressure from the reference value of 70mmHg (prone) and 40mmHg (supine) was used as the outcome measure on a Pressure Biofeedback Unit and length of time (in seconds), a correct contraction of the core stability muscles was maintained. Secondly, the length of time (in seconds) for Trunk Extensor Endurance. Thirdly, repeated measures for NRS-101 and Quebec Back Pain Disability Scale for the duration of the research period. v Results: It was found that there was no statistical evidence or convincing trend to show that the training programmes (core stability and trunk extensor endurance) increased the subjects’ core strength or trunk extensor endurance in the time allocated, although there seemed to be a placebo effect in the Trunk Extensor Group, which showed improvement in some of the core stability outcomes. There was statistical evidence that the intervention (training programmes) reduced pain, according to the Quebec Back Pain Disability Scale (Quebec) score over time, and a non-significant trend suggested this according to the Numerical Rating Scale-101 (NRS). Since both groups’ NRS and Quebec scores were not significantly different at baseline, the difference can be attributed to the effect of the intervention. Conclusions: The results of this study found that the Trunk Extensor Endurance Group, that performed the trunk extensor endurance training programme, yielded better results in core stability and trunk extensor endurance. However, the Core Stability Group, that performed the core stability training programme, showed a quicker reduction in pain levels during the three week intervention period. Therefore, by combining both training programmes, future rehabilitation of athletes suffering from acute low back pain will be more successful. Sport performance of the athletes (field hockey players), through the proponents of swiss ball training, will also improve.

published_or_final_version / Community Medicine / Doctoral / Doctor of Philosophy

Bariatric surgery has emerged as the most effective method for producing substantial long-term weight loss and inducing remission or reducing severity of many comorbidities for individuals with severe obesity. However, maintaining these successes from surgery requires that individuals combine the surgical intervention with numerous behavioral changes including dietary, physical activity, and lifestyle behaviors. Despite the positive weight and health outcomes associated with bariatric surgery, a proportion of the population experiences insufficient weight loss or weight regain, which may depend on the individual’s adherence to the bariatric behavioral recommendations. Few studies have investigated specific bariatric behaviors and whether they are impactful on weight outcomes. The purpose of this study was to (1) examine the extent to which constructs of the extended Theory of Planned Behavior (TPB) predicted six bariatric behaviors: (a) eating protein at the start of a meal, (b) eating three to five daily servings of fruits and vegetables, (c) avoiding sweet foods, (d) avoiding salty snack foods, (e) avoiding sugar sweetened beverages, and (f) exercising for 30 minutes daily at moderate to vigorous intensity; (2) to evaluate the relationship of the aforementioned behaviors with excess weight loss outcomes; and (3) to explore the facilitators and barriers successful bariatric patients identify as factors that influence their adherence to bariatric dietary and exercise behaviors. A sequential explanatory mixed methods approach was used to address the purpose of this study. The first component consisted of collecting quantitative data from bariatric patients between 6-24 months post-operative while the second was completed by collecting qualitative data from participants, who based on certain criteria, were considered to be successful one year or more after their bariatric surgeries. Quantitative component: A cross sectional design examined a convenience sample of 136 mainly female (89.7%) and Hispanic (72.1%) bariatric patients that underwent either a Roux-en-Y gastric bypass or sleeve gastrectomy in one ethnically diverse New York City hospital. Instruments for this study were developed based on previous research and translated into Spanish. Reliability estimates and content validity were assessed with a sample similar to that used in the study for both the English and Spanish instruments. The variables found in the extended TPB were assessed through instrument items that measure intention, attitudes, subjective norms, perceived behavioral control, anticipated behavioral outcomes, normative beliefs, control beliefs, and the additional constructs of anticipated emotions and self-identity in relation to the six bariatric behaviors. Adherence to bariatric behaviors was measured by a frequency instrument. Pre- and post-operative weight measures were obtained from participants’ electronic medical records. Multiple regressions were used to establish the predictors for each behavior. For each behavior, attitudes towards the behavior contributed to the model for predicting behavioral intention. On the other hand, subjective norms were not found to be predictive for all behaviors with the exception of avoiding sweet foods. Behavioral intention for all behaviors was low and mainly non-significant, suggesting other constructs may be involved in order to adhere to the behavior. The level of adherence to these six behaviors remained consistent over the 6 to 24 post-operative months. To note, participants were not adherent to fruit and vegetable consumption and physical activity recommendations. Qualitative component: A purposeful sample of 11 bariatric patients that were considered successful based on study criteria participated in in-depth, semi-structured, individual interviews using a questionnaire developed from the main theoretical constructs of the TPB. In an effort to increase the understanding of the facilitators of and barriers to adherence, the addition of constructs found in the Health Action Process Approach framework were used to identitfy emerging themes. Content analysis of audio recording revealed (a) outcome expectations, (b) nutrition knowledge and skills, (c) social support, (d) attitudes towards adherence, (e) perceived behavioral control, (f) coping and planning strategies, and (g) recovery self-efficacy as major themes that influenced participants’ behaviors. A main facilitator to adhere to bariatric recommendations was outcome expectation, as post-operative patients saw the improvements in their health and quality of life following the bariatric surgery intervention as motivators to continue following recommendations and therefore preserve positive outcomes. At the same time, many participants stated difficulty in adhering to the recommendation of exercising at a moderate or vigorous intensity for 30 minutes on a daily basis. Conclusion: Using a behavioral change theory provides a valuable framework for explaining adherence to healthy dietary and physical activity behaviors for bariatric patients. Nutrition education and behavioral interventions should focus on improving adherence to the recommendations of consuming fruits and vegetable and exercising daily, aiming to enhance attitudes towards these post bariatric surgery behaviors and addressing barriers to physical activity.

Yu Chung Wah. / "August 2002." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (p. 260-296). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

Thesis (Ph. D.)--University of California, San Diego, and San Diego State University, 2004. / Vita. Includes bibliographical references (leaves 122-130).

Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (leaves 65-68).