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PubMed2002

Monte Carlo tests of stochastic Loewner evolution predictions for the 2D self-avoiding walk.

The conjecture that the scaling limit of the two-dimensional self-avoiding walk (SAW) in a half plane is given by the stochastic Loewner evolution (SLE) with kappa = 8/3 leads to explicit predictions about the SAW. A remarkable feature of these predictions is that they yield not just critical exponents but also probability distributions for certain random variables associated with the self-avoiding walk. We test two of these predictions with Monte Carlo simulations and find excellent agreement, thus providing numerical support to the conjecture that the scaling limit of the SAW is SLE(8/3).

Journal Article↗
PubMed1994

Enhancing exercise adherence in middle-aged males and females.

BACKGROUND: Perceptions of personal efficacy have been consistently identified as being determinants of exercise adherence in asymptomatic, rehabilitative, younger, and older populations. The present study incorporated a randomized control design in an effort to examine the effects of an efficacy-based intervention in enhancing exercise adherence in a large sample (N = 114) of formerly sedentary middle-aged males and females. METHODS: Subjects randomly assigned to an exercise plus intervention group or an exercise plus attentional control group participated in a 5-month long walking program led by trained personnel. Exercise behavior (frequency, miles walked, duration) were assessed on a continuous basis and self-efficacy was measured at 1, 2, and 4 months. RESULTS: Repeated measures multivariate analyses revealed a significant treatment effect with subjects in the intervention group exercising more frequently, for longer duration, and walking greater distances over the course of the program. Path analysis indicated that the effect of the treatment on adherence was direct rather than through self-efficacy as hypothesized. Self-efficacy was, however, a significant predictor of exercise behavior in the early and middle stages of the exercise program but not during the last month. CONCLUSIONS: An intervention program designed to maximize information pertaining to participants' capabilities appears to have had a reasonable effect on reducing attrition in middle-aged males and females and self-efficacy was a significant predictor of exercise frequency over time. Further research efforts are required to tease out those cognitive factors that might underlie any effects of interventions in exercise adherence.

Attitude to Health↗
PubMed2005

Motivational interviewing to promote physical activity for people with chronic heart failure.

AIM: This paper reports a study comparing, over a 5-month period, two different methods of increasing physical activity: a traditional exercise programme and one based on motivational interviewing. BACKGROUND: Chronic heart failure is associated with poor quality of life that can be improved by increased physical activity. Patients who are directed to engage in physical activity have a record of low compliance. METHOD: Sixty older aged heart failure patients were randomly assigned to standard care, motivational interviewing or both treatments. The primary outcome was physical activity (kcal/kg/day), with the 6-minute walk test as a secondary outcome. FINDINGS: At entry, no significant differences were observed between the three groups. Following treatment, the 'motivational interviewing' and 'both treatments' groups reported an increase in their level and type of activities, whereas the 'standard care' group did not. All groups significantly increased their 6-minute walk distance. CONCLUSIONS: Motivational interviewing, which incorporates established behaviour change principles and a flexible approach to promotion of activity, increases reported physical activity in older patients with heart failure over a short period. In terms of level and type of activity, this approach gives a better outcome than standard care, and nurses should explore alternative strategies to promote health in this population.

Aged↗
PubMed2003

Reliabilities of the Groningen Functional Capacity Test.

The purpose of this study was to make a preliminary evaluation of the test-retest reliability of the Groningen Functional Capacity Test, a test developed to assess the functional capacity of people with a chronic disease and/or physical handicap and participating in a recreational sports stimulation program called SCALA, as a way to create homogeneous sport groups. The test includes motor actions typical for the SCALA sports program and has eight subtests, reaching, balancing, ball-catching, picking up objects, ball-kicking, ball-throwing accuracy, tennis, and walking. The subjects were 52 adults aged 46-71 years, randomly selected from the SCALA project. Intraclass correlations ranged from .96 to .58. Two subtests showed significant improvements on retest for walking (total sample and men) and picking up (total sample, men, and women). For most subtests, test-retest reliability was satisfactory and therefore worth being implemented in the SCALA program.

Aged↗
PubMed1999

Walking in labor.

Explore the source record for details and available documents.

Cesarean Section↗
PubMed2004

Effect of partial body weight support treadmill training in chronic stroke patients.

OBJECTIVE: To compare the effect of Partial Body Weight Support Treadmill Training (PBWSTT) technique and floor walking training, on floor walking velocities and functional balance in chronic stroke patients. DESIGN: An observer blinded, randomized controlled trial. MATERIAL AND METHOD: Forty-eight chronic stroke patients were randomized into either the experimental group that received PB WSTT (n=24) or the control group that received floor walking training (n=24). Both groups received 25 minutes of daily walking training 5 days per weeks, totally 4 weeks. Treatment outcomes were assessed on floor walking velocities and functional balance by Berg Balance Scale RESULTS: There was no statistically significant difference between both groups after a 4-week training period with regard to floor walking velocities and functional balance at p < 0.05. Patients in both groups had statistically significant improvement in these variables after a 4-week training period when compared to before training at p < 0.05. CONCLUSION: The efficacy of PBWSTT in chronic stroke patients was not statistically different to the efficacy of floor walking training in floor walking velocities and functional balance.

Adult↗
PubMed2004

Successful recruitment and retention strategies for a randomized weight management trial for people with diabetes living in rural, medically underserved counties of South Carolina: the POWER study.

We evaluated the feasibility of recruiting overweight adults with diabetes, living in rural, medically underserved communities, to a weight management intervention consisting of a 12-month clinical trial of two weight management programs and usual care. The sampling frame consisted of adults ages 45 years and older with clinically diagnosed diabetes from two community health centers. The recruitment process included medical record review, prescreening telephone call, two screening visits, and a randomization visit. Over 1,400 medical records were reviewed; 78.6% met eligibility criteria; 60.1% were contacted for telephone prescreening, and 35.5% remained eligible and were interested in participating. Of these, 187 completed visit 1, 164 completed visit 2, and 143 were randomized. Forty-six people were randomized who entered the study as walk-ins at screening visit 1, resulting in 189 subjects. The final yield was 21.5%. Subject mean age was 60.4 years, mean body mass index was 36.4 kg/m(2), 80% were African-American, and 46.6% had less than a high school education. Retention at 12 months was 81.5%. Successful strategies included partnering with community health centers, positive reinforcement and social supportiveness, monitoring progress, and free transportation. This work provides a useful example of an academic-community partnership designed to reach groups previously considered hard to reach.

Black or African American↗
PubMed2002

Walking trials in postmenopausal women: effect of one vs two daily bouts on aerobic fitness.

We compared the effects of one vs two daily bouts of walking on aerobic fitness and body composition in postmenopausal women. One hundred and thirty-four subjects were randomized into exercise groups or a control group and 130 completed the study. The subjects walked 5 d/week for 15 weeks at 65% of their maximal aerobic power expending 300 kcal (1255 kJ) in exercise in one (Group S1) or two daily sessions (Group S2). VO(2max) was measured in a direct maximal treadmill test. Body mass index (BMI) was calculated and the percentage of body fat (fat%) estimated using skinfold measurements. The net change in the VO(2max) was 2.5 mL min/kg (95% CI 1.5, 3.5) (8.7%) in Group S1 and 2.5 mL min/kg (95% CI 1.5, 3.5) (8.8%) in Group S2. The net change in body mass was -1.2 kg (95% CI-1.9, -0.5) in Group S1 and -1.1 kg (95% CI -1.8, -0.4) in Group S2. The net fat% change was -2.1% (95% CI-2.7, -1.4) in Group S1 and -1.7% (95% CI-2.3, -1.0) in Group S2. Exercise improved the maximal aerobic power and body composition equally when walking was performed in one or two daily bouts.

Body Composition↗
PubMed1996

Exercise training decreases dyspnea and the distress and anxiety associated with it. Monitoring alone may be as effective as coaching.

STUDY OBJECTIVE: To determine whether exercise training with coaching is more effective than exercise training alone in reducing dyspnea and the anxiety and distress associated with it and improving exercise performance, self-efficacy for walking, and dyspnea with activities of daily living. DESIGN: Randomized clinical trial of 51 dyspnea-limited patients with COPD assigned to monitored (n = 27) or coached (n = 24) exercise groups. SETTING: Outpatient area of university teaching hospital. INTERVENTION: Both groups completed 12 supervised treadmill training sessions (phase 1) over 4 weeks followed by 8 weeks of home walking (phase 2). The CE group also received coaching during training. MEASUREMENTS: Perceived work of breathing, dyspnea intensity, distress associated with dyspnea, and anxiety associated with dyspnea were rated on a visual analog scale during incremental treadmill testing and after 6-min walks before and after phase 1. Dyspnea with activities of daily living, self-efficacy for walking, state anxiety, and 6-min walks were measured before and after both phases. RESULTS: Dyspnea and the associated distress and anxiety improved significantly for both groups relative to work performed and in relation to ventilation (p < 0.05). There were no significant differences between groups in any outcomes. The phase 1 improvement in laboratory dyspnea was accompanied by improvements in dyspnea with activities of daily living (p < 0.01) and self-efficacy for home walking (p < 0.01) that were sustained during the home phase. CONCLUSIONS: Coaching with exercise training was no more effective than exercise training alone in improving exercise performance, dyspnea, and the anxiety and distress associated with it, dyspnea with activities, and self-efficacy for walking.

Aged↗
PubMed2005

Features of the neighborhood environment and walking by U.S. adults.

BACKGROUND: Manipulating the physical environment may be an efficacious way to promote physical activity. This study examined the relationships between features of the neighborhood environment and walking in the neighborhood by U.S. adults. METHODS: A random sample of women (n =266) and men (n =208) aged >18 years participated. Door-to-door interviews were conducted in 2003 to collect information about demographics, walking behavior, and features of the neighborhood environment. RESULTS: The analyses conducted in 2004 revealed that women were more likely to walk for exercise (odds ratio [OR]=4.6, 95% confidence interval [CI]=1.01-20.72) or walk a dog (OR=3.3, 95% CI=1.01-11.08) in the neighborhood if neighborhood safety was average as opposed to below average (p <0.05). Women with an average number of neighborhood destinations were more likely to walk for transportation in the neighborhood (OR=5.7, 95% CI=1.63-19.73) than women with a below average number of neighborhood destinations (p <0.01). In men, none of the neighborhood features were significantly associated with walking for exercise or walking a dog. Men were less likely to walk for transportation in the neighborhood if the functional (OR=0.22, 95% CI=0.06-0.89) or aesthetic (OR=0.17, 95% CI=0.03-0.89) features of the neighborhood were average versus below average. CONCLUSIONS: Prospective studies are needed to determine if changes in neighborhood safety and awareness of neighborhood destinations promote increases in walking by women. Evaluations of the relationships between other environmental features and walking behavior in men are warranted.

Adult↗
PubMed2007

Effect of multilevel botulinum toxin a and comprehensive rehabilitation on gait in cerebral palsy.

To evaluate the effect of multilevel botulinum toxin A and comprehensive rehabilitation on gait pattern, muscle length, and spasticity, a multicenter randomized trial was performed in 46 children with spastic cerebral palsy who walk with flexed knees. Their mean age was 8.0 years (range 4 to 11 years). They were randomly allocated to the intervention group (multilevel botulinum toxin A and comprehensive rehabilitation) or the control group (usual care). After 6 weeks, a significant treatment effect in the intervention group was observed on: improved knee extension during midstance and terminal swing (7 degrees and 5 degrees , P < 0.01, respectively); hip rotation during terminal swing (4 degrees , P = 0.02); gait score (1.7, P < 0.01); decreased spasticity in hamstrings (11 degrees , P < 0.01), gastrocnemius (6 degrees , P = 0.01), and soleus (5 degrees , P = 0.02); and increased muscle length in hamstrings (9 degrees , P < 0.01) and gastrocnemius (5 degrees , P < 0.01). The improved muscle length was maintained up to 24 weeks. This study demonstrated that multilevel botulinum toxin A and comprehensive rehabilitation improves knee extension during gait, increases muscle length, and decreases spasticity in injected muscles after 6 weeks in children who walk with flexed knees. Although the effect on muscle length was maintained after 24 weeks, the effect on gait and spasticity had disappeared.

Botulinum Toxins, Type A↗
PubMed2005

Effects of regular physical activity on defecation pattern in middle-aged patients complaining of chronic constipation.

OBJECTIVE: It is not well known whether physical activity (PA) is useful in the management of patients complaining of constipation. The aim of this study was to test the influence of regular PA on colonic transit time and defecation in middle-aged inactive patients suffering from chronic idiopathic constipation. MATERIAL AND METHODS: Forty-three subjects (> 45 years) were randomly divided into group A (n = 18, 16 F, 2 M) and group B (n = 25, 20 F, 5 M). Group A subjects maintained their normal lifestyle during 12 weeks, followed by a 12-week PA programme. Group B performed a 12-week PA programme after randomization. PA comprised 30 min of brisk walking and a daily 11-min home-based programme. Both groups received dietary advice. Colonic transit time was measured using a radiographic multiple marker single film technique. RESULTS: Despite dietary advice, mean fibre and fluid intake did not change. In group B a significant reduction in 3 out of 4 of the Rome I criteria for constipation was observed, i.e. percentage of incomplete defecations, percentage of defecations requiring straining and percentage of hard stools (p < 0.05). As a consequence, the number of fulfilled Rome criteria for constipation decreased (2.7 to 1.7; p < 0.05). Furthermore, the rectosigmoid and total colonic transit time decreased (17.5 to 9.6 h and 79.2 to 58.4 h, respectively; p < 0.05). After PA the number of fulfilled Rome criteria also decreased in group A (2.6 to 1.7; p < 0.05). CONCLUSIONS: In middle-aged inactive subjects with symptoms of chronic constipation, it is advisable to promote regular physical activity since it improves both the defecation pattern and rectosigmoid or total colonic transit time.

Age Factors↗
PubMed2004

Effects of lead and exercise on endurance and learning in young herring gulls.

In this paper, we report the use of young herring gulls, Larus argentatus, to examine the effect of lead and exercise on endurance, performance, and learning on a treadmill. Eighty 1-day-old herring gull chicks were randomly assigned to either a control group or a lead treatment group that received a single dose of lead acetate solution (100mg/kg) at day 2. Controls were injected with an equal volume of isotonic saline at the same age. Half of the lead treatment group and half of the control group were randomly assigned to an exercise regime of walking on a treadmill twice each day. The other group remained in their cages. We test the null hypotheses that neither lead nor exercise affected performance of herring gull chicks when subsequently tested on the treadmill at 7, 11, and 17 days post-injection. Performance measures included latency to orient forward initially, to move continuously, forward on the treadmill, and to avoiding being bumped against the back of the test chamber. Also measured were the number of calls per 15 s, and the time to tire out. Latency to face forward and avoiding being bumped against the back of the test chamber were measures of learning, and time to tire out was a measure of endurance. We found significant differences as a function of lead, exercise, and their interaction, and rejected the null hypotheses. For all measures of behavior and endurance, lead had the greatest contribution to accounting for variability. In general, lead-treated birds showed better performance improvement from the daily exercise than did controlled non-lead birds, with respect to endurance and learning. We suggest that in nature, exercise can improve performance of lead-exposed birds by partially mitigating the effects of lead, thereby increasing survival of lead-impaired chicks.

Animals↗
PubMed2000

Will patients use a computer to give a medical history?

BACKGROUND: A patient-entered computerized history, can be used as a means of medical data collection in a large inner city population. We evaluated whether a patient presenting to the Charity Hospital campus of the Medical Center of Louisiana in New Orleans would use a computer to provide medical information. OBJECTIVE: To determine whether patients would self-administer a computerized medical history and find this an acceptable experience DESIGN: A survey questionnaire was given to 100 patients selected from the emergency department walk-in clinic waiting area. SETTING: Charity Hospital emergency room walk-in clinic METHODS: One hundred patients older than 18 years were selected to give a random sample of the population using the Charity Hospital emergency room walk-in clinic for care. The patients received a questionnaire for rating their experience with the computer. Demographics were collected for all patients, including the 13 who declined participation. The main outcome was the patient's perception of the acceptability of using the computerized medical history. A second important outcome measure was patient refusal to participate in the study. RESULTS: Our analysis of the acceptability ratings revealed adequate internal validity (Cronbach alpha=0.75). A single total score was created for these ratings. The participants' scores ranged from 2.0 to 4.0, with a mean of 3.3 (standard error of the mean=0.04). We observed an 83% positive experience in the participating population. CONCLUSIONS: The patients were able to use the computer to enter their medical information. They responded favorably to the experience and appeared to be capable and willing to provide medical information through use of this technology.

Adolescent↗
PubMedDate not supplied

Effects of endurance training on selected parameters of immune function in elderly women.

BACKGROUND: Immune function decreases with age, rendering the elderly more susceptible to infection and tumor development. In addition, intense exercise has been shown to decrease immune function in some populations. Few studies have examined the effects of exercise on immune function in the elderly and, to our knowledge, no studies have examined the effects of exercise on a population of active, but nonexercising elderly. OBJECTIVE: The purpose of this study was to examine the effects of a 10-week endurance training program on selected parameters of immune function in active elderly women. METHODS: A total of 29 healthy, active women, aged 70-87, were randomly assigned to either an exercise (76 +/- 5 years, n = 15) or control (77 +/- 6 years, n = 14) group. The exercise group walked 3 days/week at 70% heart rate reserve (HRR). The duration on day 1 was 20 min and it was increased by 5 min each day until subjects were walking for 50 min (week 3). It remained at 50 min for the duration of the study, while controls maintained normal activity. Blood samples were obtained from both groups at rest, and from the exercise group after 20 min of walking at 70% HRR and after 2 h of recovery. Blood samples were collected prior to endurance training and again after 10 weeks of endurance training. RESULTS: There was a significant decrease in 1-mile walk times as well as heart rate at completion of the walk in the exercise group. Natural cell-mediated cytotoxicity (NCMC) was significantly higher post-exercise, compared to pre-exercise both before and after training. After training it remained significantly elevated 2 h post-exercise. The resting NCMC was significantly decreased in controls at week 10 but not in the exercise group. CONCLUSION: Ten weeks of endurance training resulted in a significant decrease in both the 1-mile walk time and the post-walk heart rate in the exercisers but not the controls, without resulting in either an acute or chronic suppression of immune function. Further, endurance training may lead to an attenuation of the decrease in cellular immune measures which occurs during the winter, since the control group experienced a decrease in NCMC and the exercisers did not.

Aged↗
PubMed2004

Differences in normal and perturbed walking kinematics between male and female athletes.

OBJECTIVE: To identify differences in lower extremity kinematic movement patterns between genders during walking through the application of an expected perturbation. DESIGN: Randomized limb kinematics were compared between healthy active males and females. BACKGROUND: Lower extremity kinematics during jump landing and cutting have been implicated as a potential source of the discrepancy in anterior cruciate ligament injury rates between genders. Kinematic differences between genders have been identified during tasks that are not provocative of anterior cruciate ligament injury but do result in increased ligament strain. Repetition of movement patterns that increase anterior cruciate ligament strain may increase the likelihood they will be reproduced during athletic tasks that produce force loads that exceed anterior cruciate ligament tensile strength. METHODS: Twenty subjects (10 women, 10 men) classified as a level I or II athlete underwent motion analyses while performing self-paced walking trials. Five trials were undisturbed, and five each with a platform translating either laterally or anteriorly at heel contact. Sagittal, frontal, and transverse hip angles as well as sagittal and frontal knee angles were collected during stance. RESULTS: Excursions in the frontal and transverse planes were greater at the hip and knee for females compared to males in each walking condition. The rate of these excursions also occurred more rapidly for females than males. There was no difference for joint angles at initial contact between genders, and there was no difference in the amount of sagittal plane excursion for the hip and knee when comparing genders. CONCLUSIONS: Females demonstrate characteristics during both normal and perturbed gait that may potentially contribute to increased anterior cruciate ligament strain. Repetition of these potentially harmful movement patterns during provocative athletic maneuvers may lead to anterior cruciate ligament injury. RELEVANCE: Females exhibit lower extremity kinematic patterns that differ from males. Female kinematic patterns may contribute to an increased risk for anterior cruciate ligament injury.

Adaptation, Physiological↗
PubMed1999

European multicenter study on propionyl-L-carnitine in intermittent claudication.

OBJECTIVES: This study was performed to identify a target population of claudicants for propionyl-L-carnitine treatment. BACKGROUND: Previous studies suggest that the efficacy of propionyl-L-carnitine in intermittent claudication is greater in patients with severe functional impairment than in those with mild walking disability. METHODS: After run-in, 485 claudicant patients were randomized to placebo or propionyl-L-carnitine (1 g bid, p.o.) and then stratified on the basis of maximal walking distance (cutoff point 250 m) and maximal walking distance variability (cutoff point 25%). Treatment lasted 12 months. Walking capacity was assessed by treadmill and quality of life by a questionnaire exploring various aspects of daily life. RESULTS: In the target population, that is, patients who at baseline walked < or = 250 m and showed a maximal walking distance variability < or = 25%, per-protocol analysis showed that the effect of propinyl-L-carnitine was significantly greater than that with placebo for both maximal walking distance and initial claudication distance (ICD). In the intention-to-treat population, maximal walking distance increased by 62 +/- 14% on propionyl-L-carnitine and by 46 +/- 9% (p < 0.05) on placebo, while no difference between treatments was observed for ICD. The beneficial effect of propionyl-L-carnitine was confirmed when data of the target population were pooled with those of patients who at baseline walked < or = 250 m and showed a > 25% maximal walking distance < 50% variability. Actually, maximal walking distance increased by 98 +/- 16% in the propionyl-L-carnitine group and by only 54 +/- 10% in the placebo group (p < 0.01). The corresponding values for ICD were 99 +/- 21% and 51 +/- 8% (p < 0.05). For patients with baseline maximal walking distance > 250 m, no difference between treatments was observed. CONCLUSIONS: Claudicants with maximal walking distance < or = 250 m benefited from the use of propionyl-L-carnitine, with improvement in walking distance and quality of life. However, patients with mild functional impairment (i.e., walking distance > 250 m) showed no response to propionyl-L-carnitine.

Cardiotonic Agents↗