The purpose of this investigation was to determine the effects of a 12-week progressive resistance training program (PRT) on single myofiber calcium sensitivity in older women. Five healthy older women between the ages of 67-82 with a mean age of 72.8±2.7 yr. participated in this study. The training regimen consisted of bilateral isotonic knee extensions. The subjects performed 3 sets, the first two sets consisted of 10 repetitions and the last set was performed to volitional exhaustion at 80% of their 1RM 3 days/week. Muscle biopsies of the vastus lateralis were obtained and single muscle fibers were isolated. The fibers were mounted and fiber length and diameter were determined. The experimental sequence for each fiber was the determination of maximal isometric tension (PO) at pCa 4.5 (pCa = -log [Ca 2+]), and then subsequent activations of the fiber submaximally with free Ca 2+ concentrations of pCa 6.8, 6.5, 6.2, 6.0, 5.8, 5.5, 5.2, 5.0, and 4.7. Due to the small sample size of the myosin heavy chain (MHC) type II single fibers that were studied, only the MHC type I fibers were included for analysis. The MHC type I single fiber diameter increased significantly (p<0.05) from 90.47±3.90 µm to 102.47±2.27 gm pre-to-post PRT, respectively. The Po increased approximately 22% (p<0.05) in the MHC type I fibers pre- to-post PRT. The mean MHC type I fiber Ca 2+ activation threshold increased (p<0.05) from pCa 6.83±0.02 to pCa 6.91±0.01 preto-post PRT. In addition, the mean half-maximal activation of the type I fibers increased (p<0.05) with PRT (5.50±0.02 and 5.70±0.03, pre and post, respectively. The slope of the tension-pCa relationship below (n2) and above (ni) half-maximal activation were also examined to predict molecular cooperativity during cross-bridge interaction. The slope of the Hill plot for n1 did not change significantly with the PRT. However, the slope of the Hill plot for n2 demonstrated a significant increase (p<0.05) from 1.70±0.11 to 2.43±0.09 pre-to-post PRT. In conclusion, the results of this investigation indicate that myofibril Ca 2+ sensitivity and activation properties appear to exhibit a significant role in the mechanisms involved with skeletal muscle adaptability in older women following PRT. / School of Physical Education

The purpose of this study was to determine how walking with T-Poles, training using T-Poles and increased walking speed would change GRF measures in elderly subjects. The magnitudes of peak force, average force, and impulse force variables decreased as a result of the T-Pole use. Time during support phase increased when using T-Poles. The magnitudes of peak force, average force, and impulse force, and time variables decreased with extended training using T-Poles. However, loading rate increased with training and practice. FZ3, AZP, and AZ showed interactions between T-Pole use and training and TP showed an interaction between T-Pole use and walking speed. The results of this investigation suggest that using T-Poles generally reduces foot-ground force interaction during walking. It is a tendency that the foot-ground interactions during walking with TPoles decreased more with the longer period of T-Pole use and significant interactions between T-Pole use and training were observed in AZ3, AZP, and AZ. The reductions of foot-ground interaction induced by the T-Pole and practice time using T-Poles were present regardless of increased walking speed. / School of Physical Education

Findings were that caregivers considered all items on the Information Needs and Patient Care Needs subscales to be important but most of the unmet needs were from the Patient Care subscale. The needs less satisfied in relation to importance were (a) ways to improve patient appearance, (b) activities that will make patient feel purposeful, (c) information on how to give medications, (d) ways to reassure patient, (e) ways of coping with patient's diagnosis, (f) ways to dress patient comfortably, (g) ways to deal with patient's decreased energy, and (h) importance of not leaving patient alone.The implications for nursing are to assess and anticipate the needs of the caregiver of the stroke survivor so that his or her needs can be met. Preparing caregivers for their new role by meeting their needs will help the nurse met the primary goal of helping the patient. / School of Physical Education

The purpose of this study was to investigate whole muscle and single muscle fiber adaptations in old men (OM) and old women (OW) over 80 years of age in response to progressive resistance training (PRT). Six OM (82±1 y, 74±4 kg, BMI 25±1 kg•m-2) and six OW (85±1 y, 67±3 kg, BMI 27±1 kg•m-2) resistance trained the knee extensors (3 sets, 10 repetitions) at 70% one repetition maximum 3 d•wk-1 for 12 wks. Vastus lateralis muscle biopsies were obtained before and after the PRT program. Isolated muscle fibers were studied in vitro at 15°C for diameter (Dia), peak tension (Po), unloaded shortening velocity (Vo), and absolute peak power (Abs Pwr). With PRT, OM increased whole muscle strength (40±6%, p<0.05), with no change in whole muscle size. OW also increased whole muscle strength (26±6%, p<0.05) without a change in whole muscle size. No differences were observed in any of the single muscle fiber parameters among MHC I or MHC IIa muscle fibers from OM or OW. The novel finding of this study was that despite an increase in whole muscle strength there was no change in whole muscle size, single fiber diameter, or single fiber contractile function. Given that there was no change in muscle size or cellular function with PRT, the improvement in whole muscle strength point to neurological changes. These data suggest that the hypertrophic mechanisms that are typically apparent in humans with PRT are attenuated in individuals over 80 y. / School of Physical Education, Sport, and Exercise Science

Eight sedentary elderly subjects (X̅ age = 83.4yr), including two males and six females, were evaluated to determine the effects of a low intensity, chair-based exercise program on selected physiological parameters. Exercise sessions were held 3 alternate days per week, 45 minutes per session, for 8 weeks. Subjects were exercise tested before and after training using a modification of the Smith and Gilligan chair step test; this is a multi-level graded exercise test suitable for very old subjects with aerobic exercise capacities of approximately 2-4 METs. Upon completion of training, group data analyses showed no significant adaptations in resting heart rate or blood pressure, exercise heart rate or blood pressure, peak exercise performance, nor for subject rating of perceived exertion at a fixed exercise intensity. A significant increase (p < 0.05) was observed post-training in the immediate post-exercise blood lactic acid response. Separating subjects (n=4) into high (91% attendance) and moderate (49% attendance) compliers, statistically significant differences were found for training related changes in several physiological parameters. Between-group analysis also showed significant changes (p < 0.05) in the chair exercise performance time. Post-training, the high compliers improved their total exercise tolerance (time) by 33%, whereas the moderate compliers exercise time was 22% less as compared to pre-training. A significant difference (p < 0.05) was also observed between groups in their perception of effort at a fixed-load in the exercise test. After training, the high compliers judged their effort to be 12% less at a fixed load in the chair exercise test, while the moderate compliers showed no significant changes (p < 0.05). Blood lactic acid responses were significantly higher (p < 0.05) after training for the high compliance group but no such change was found in the HLa response of the moderate compliers. There were no significant changes in resting or exercise heart rate and blood pressure responses in either the high or moderate compliance groups. The results of this study suggest that physiological adaptations do not occur in old individuals in response to a low intensity exercise program. Given these preliminary findings, further investigations are indicated to determine the effects of increased frequency and duration of physical activity programs on additional physiological parameters. / Master of Science

Psychological stress is common and contributes to many physical and mental health problems. Its effects are mediated by a complex neurobiological system centering in the brain with effectors including autonomic nervous system, hypothalamic-pituitary-adrenal axis, inflammatory system, and gene expression. A stressor pushes the human physiological system away from its baseline state towards a lower utility state. The physiological system may return towards the original state but may be shifted to a lower utility state. While some physiological changes induced by stressors may benefit health, chronic stressors usually have negative effects on health. In contrast to this stressor effect is the system's resilience which influences its ability to return to the high utility attractor basin following a perturbation by increasing the likelihood and/or speed of returning to the baseline state following a stressor. Age-related cognitive decline is a major public health issue with few preventative options. Stress contributes to this cognitive decline, and mindfulness meditation (MM) is a behavioral intervention that reduces stress and stress reactivity in many health conditions. A randomized clinical trial was performed to determine if MM in older adults would improve measures of cognitive function, as well as psychology and physiology, and to determine what factors might predict who would improve. 134 at least mildly stressed 50-85 year olds were randomized to a MM intervention or a wait-list control. Outcome measures included a broad cognitive function battery with emphasis on attention and executive function, self-rated psychological measures of affect and stress, and physiological measures of stress. Self-rated measures related to negative affect and stress were all significantly improved as a result of the MM intervention compared to wait-list control. There were no changes in cognition, salivary cortisol, and heart rate variability. Potential explanations for the discrepancy between the beneficial mental health outcomes and lack of impact on cognitive and physiological outcomes are discussed. To determine which factors predict MM responsiveness, a responder was defined by determining if there was a minimum clinically important improvement in mental health. Predictors included demographic information and selected self-rated baseline measures related to stress and affect. Classification was performed using decision tree analysis. There were 61 responders and 60 non-responders. Univariate statistical analysis of the baseline measures demonstrated significant differences between the responder and non-responders in several self-rated mental health measures. However, decision tree was unable to achieve a reliable classification rate better than 65%. A number of future research directions were suggested by this study, including to optimize the MM intervention itself, to better select participants who would benefit from MM, and to improve the outcome measures perhaps by focusing on decreased reactivity to stressful events. Finally, a less well-defined but always present future research direction is the development of better models and better quantitative analysis approaches to the multivariate but dynamically limited human empirical data that can be practically collected.

Thesis (M Sport Sc)--Stellenbosch University, 2007. / ENGLISH ABSTRACT: Global aging is occurring at an unprecedented rate. South Africa has the highest proportion of older adults in Southern Africa, with nearly 7% of the population over the age of 60 years in 1997. However, although people are living longer, statistics show that they are not necessarily living healthier. The majority of women who outlive men have to deal with more chronic diseases as well as a poorer functional status than the latter. The purpose of the present study was to implement a movement competence programme suited to the needs of South African older adult women; requiring inexpensive apparatus and that can be performed in any environment. A time-series design was used which included follow up testing 9 months after the cessation of the movement competence programme. The intervention group consisted out of 21 (76.14±5.44 years) older adult women, who were randomly selected from a retirement village. The movement competence programme was broad based in nature and was performed in two one hourly sessions a week for 12 weeks. After pre-tests of functional capacity, selfperception and resilience, the older adult women were tested using the Physical Self-Perception Profile (Fox & Corbin, 1989) and the Resilience Scale (Connor & Davidson, 2003) respectively. Significant improvements (p<0.05) were observed in the Berg Balance Scale, 8-Foot Up-and-Go and the Physical Self-Perception’s results of the older adult women. No significant (p>0.05) difference was noted in the Barthel Index and Resilience Scale after the 12-week movement competence programme. Follow up testing indicated a significant improvement in the resilience of the older adult women who continued to exercise, compared to those that chose a sedentary lifestyle after the movement competence programme. / AFRIKAANSE OPSOMMING: Globale veroudering vind teen ’n ongekende tempo plaas. Suid-Afrika beskik oor die hoogste verhouding ouer volwassenes in Suidelike Afrika met amper 7% van die populasie in 1997 ouer as 60 jaar. Hoewel mense egter langer lewe toon statistiek dat hulle nie noodwendig gesonder lewe nie. Die meerderheid dames wat langer lewe as mans het te kampe met meer chroniese siektes asook ’n swakker funksionele status as dié van laasgenoemde. Die doel van die huidige studie was om ’n bewegingsbevoegdheidsprogram te implementeer wat aan die behoeftes van ouer Suid-Afrikaanse volwasse dames voldoen, waar goedkoop toerusting benodig word en in enige omgewing uitgevoer kan word. ’n “time-series” ontwerp was gebruik wat opvolgtoetse ingesluit het nege maande ná die beëindiging van die bewegingsbevoegdheidsprogram. Die intervensiegroep het bestaan uit 21 (76.14±5.44 jaar) ouer volwasse dames wat lukraak geselekteer is by ’n aftree-oord. Die bewegingsbevoegdheidsprogram was breed in fokus en was uitgevoer in twee eenuurlikse sessies per week vir 12 weke. Ná voortoetse oor funksionele kapasiteit, selfpersepsie en veerkrag, is die ouer volwasse dames getoets deur respektiewelik gebruik te maak van die Fisieke Selfpersepsie Profiel (Fox & Corbin, 1989) en die Veerkragskaal (Connor & Davidson, 2003). Beduidende verbeterings (p<0.05) van die ouer volwasse dames is waargeneem in die Berg Balansskaal, “8-Foot Up-and-Go” en die resultate op die Fisieke Selfpersepsie. Geen beduidende (p>0.05) verskil is waargeneem in die Barthel Indeks en Veerkragskaal ná die 12 weke aanbieding van die bewegingsbevoegdheidsprogram nie. Opvolgtoetse het ’n beduidende verbetering aangedui in die veerkrag van die ouer volwasse dames wat aangehou het met oefening in teenstelling met dié wat gekies het om ’n sedentêre leefstyl te volg nadat die bewegingsbevoegdheidsprogram voltooi is.