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Treatment of intermittent claudication with beraprost sodium, an orally active prostaglandin I2 analogue: a double-blinded, randomized, controlled trial.

OBJECTIVES: In the current study, we hypothesized that beraprost would: 1) improve treadmill exercise performance and quality of life; and 2) decrease rates of ischemic events in patients with intermittent claudication. BACKGROUND: Previous trials with beraprost sodium, an orally active prostaglandin I(2) analogue, in the treatment of claudication in patients with peripheral arterial disease (PAD) have been inconsistent. METHODS: Patients with intermittent claudication (n = 897) were randomized to receive either 40 microg three times a day of beraprost with meals (n = 385) or placebo (n = 377) in a double-blinded manner for one year. The primary efficacy parameter was treadmill-measured maximum walking distance, as assessed at three and six months after randomization. Secondary efficacy parameters included treadmill-measured pain-free walking distance and change in quality of life. RESULTS: There was no significant improvement in maximum walking distance in the beraprost group (16.7%) as compared with the placebo group (14.6%, p = NS). Administration of beraprost did not improve the pain-free walking distance (p = NS between treatment groups), and there was no improvement in the quality-of-life measures between the treatment groups. The incidence of critical cardiovascular events was 7.3% in the beraprost group and 11.4% in the placebo group (p = NS). There was a significant reduction in the combination of cardiovascular death and myocardial infarction in the beraprost group (p = 0.01). CONCLUSIONS: Despite previous investigations suggesting efficacy, these results indicate that beraprost is not an effective treatment to improve symptoms of intermittent claudication in patients with PAD. The potential benefit of beraprost on critical cardiovascular events would require confirmation in a larger prospective investigation.

Administration, Oral↗

Placebo-controlled study of rTMS for the treatment of Parkinson's disease.

The objective of this study is to assess the safety and efficacy of repetitive transcranial magnetic stimulation (rTMS) for gait and bradykinesia in patients with Parkinson's disease (PD). In a double-blind placebo-controlled study, we evaluated the effects of 25 Hz rTMS in 18 PD patients. Eight rTMS sessions were performed over a 4-week period. Four cortical targets (left and right motor and dorsolateral prefrontal cortex) were stimulated in each session, with 300 pulses each, 100% of motor threshold intensity. Left motor cortex (MC) excitability was assessed using motor evoked potentials (MEPs) from the abductor pollicis brevis. During the 4 weeks, times for executing walking and complex hand movements tests gradually decreased. The therapeutic rTMS effect lasted for at least 1 month after treatment ended. Right-hand bradykinesia improvement correlated with increased MEP amplitude evoked by left MC rTMS after individual sessions, but improvement overall did not correlate with MC excitability. rTMS sessions appear to have a cumulative benefit for improving gait, as well as reducing upper limb bradykinesia in PD patients. Although short-term benefit may be due to MC excitability enhancement, the mechanism of cumulative benefit must have another explanation.

Evoked Potentials, Motor↗

Intra-articular hyaluronic acid after knee arthroscopy: a two-year study.

Arthroscopic knee joint lavage is used when conservative treatment of knee osteoarthritis is unsatisfactory and a joint prosthesis is not yet indicated. The potentially negative effect of irrigation fluids on cartilage metabolism and structure has led to the development of a temporary synovial fluid substitute containing hyaluronic acid. The short and long-term effects of this synovial fluid substitute were investigated in a total of 80 patients with persistent knee pain. Forty patients underwent arthroscopic knee joint lavage, in some cases combined with careful cartilage debridement (group A) while a further 40 patients underwent the same procedure which, after final joint lavage, was immediately followed by a single instillation of 10 ml of the synovial fluid substitute (0.5% sodium hyaluronate) into the joint (A + HA group). After the procedure, pain on walking and restricted ability to walk 100 m were markedly reduced to a comparable extent in both groups. Three months later, the effect of the treatment assessed using various parameters (CGI, restricted ability to walk 100 m, pain on walking, night pain) had decreased in group A, while it remained stable or even improved slightly in the A + HA group. The Mann-Whitney statistics revealed a descriptive superiority for the A + HA group at this time point. One year after treatment the superiority of the A + HA group was confirmed using the same assessment parameters. No side effects or adverse events were observed for either treatment procedure. This study shows that arthroscopic knee joint lavage leads to a lasting improvement in pain and functional impairment. The post-arthroscopic instillation of a HA-based synovial fluid substitute into the joint is a suitable way of achieving long-term stabilisation of the treatment outcome. This was supported by findings of a survey of 66 patients at 2 years after treatment in this study. Level I prospective, randomised controlled double-blind study.

Adjuvants, Immunologic↗

Acute effects of self-paced walking on urges to smoke during temporary smoking abstinence.

RATIONALE: Recent research highlights the need to extend our understanding of how exercise may aid smoking cessation, through exploration of different modes, intensity and duration of exercise. OBJECTIVES: The purpose of the study was to examine the effects of a 1-mile self-paced walk on different measures of urges to smoke following temporary smoking abstinence. METHODS: In a within-subject counterbalanced design, following 15 h of smoking abstinence, participants (N=15) exercised or sat passively on separate days. A single-item measure of strength of desire to smoke was administered during, immediately post, and at 10 and 20 min post-treatment. The two-factor Questionnaire for Smoking Urges, involving intention and desire to engage in smoking behaviour which is anticipated as pleasant, enjoyable and satisfying (desire-behave), and anticipation of relief from negative affect through smoking (desire-affect relief), was administered before and 20 min post-treatment. RESULTS: A two-way repeated-measures MANOVA revealed a significant overall interaction effect for time by condition for strength of desire to smoke, and the two QSU scales. Two-way repeated-measures univariate ANOVAs revealed significant interaction effects for time by condition for each of the three urges to smoke measures. Planned contrasts revealed that exercise reduced cigarette cravings for up to 20 min after exercise, in comparison with the control condition. ANCOVAs revealed mixed support for independent effects of exercise on all measures of urges to smoke. CONCLUSION: A self-paced walk, at a low intensity, lasting 15-20 min can have a rapid and measurable positive effect on both single and multi-item measures of urges to smoke, lasting at least 20 min, during temporary smoking abstinence.

Adolescent↗

Haemodynamic effects of dual-chamber pacing versus ventricular pacing during a walk test in patients with depressed or normal left ventricular function.

PURPOSE: Dual-chamber rate-modulated pacing provides haemodynamic benefits compared with ventricular pacing at rest, but it is unclear whether this also holds true during physical exercise in patients with heart failure. This study assessed the haemodynamic response to a walk test during dual-chamber pacing and ventricular pacing in patients with depressed or normal left ventricular (LV) function. METHODS: Twelve patients with an LV ejection fraction <50% and 11 patients with an LV ejection fraction >or=50% underwent two randomised 6-min walk tests under dual-chamber rate-modulated pacing and ventricular pacing at a fixed rate of 70 beats/min. All patients had a dual-chamber pacemaker implanted for complete heart block. LV function was monitored by a radionuclide ambulatory system. RESULTS: In patients with depressed LV function, the change from dual-chamber pacing to ventricular pacing induced a decrease in end-systolic volume at the peak of the walk test (P<0.05), with no difference in end-diastolic volume. As a consequence, higher increases in LV ejection fraction (P<0.0001) and stroke volume (P<0.01) were observed during ventricular pacing. No difference in cardiac output was found between the two pacing modes. In patients with normal LV function, the change from dual-chamber pacing to ventricular pacing induced a significant decrease in cardiac output (P<0.005 at rest and P<0.05 at the peak of the walk test). CONCLUSION: Compared with dual-chamber rate-modulated pacing, ventricular pacing improves cardiac function and does not affect cardiac output during physical activity in patients with depressed LV function, whereas it impairs cardiac output in those with normal function.

Aged↗

The effect of insoles on the incidence and severity of low back pain among workers whose job involves long-distance walking.

The prevalence and incidence of low back pain in general society is high. Workers whose job involves walking long distances have an even higher tendency to suffer from low back pain. A positive effect of insoles in reducing low back pain was found in professional sports players. This was not examined on people whose job involves walking long distances. In this double blind prospective study we examined the effectiveness of insoles constructed in a computerized method to placebo insoles in 58 employees whose work entailed extensive walking and who suffered from low back pain. The evaluation was performed by the MILLION questionnaire, which is considered as a valid questionnaire for evaluation of low back pain. We calculated the differences of the pain intensity before and after the intervention, in the employees using the insoles manufactured by computer in comparison to the users of the placebo insoles. In each group, the analysis was performed in comparison to the baseline. A total of 81% of the employees preferred the real insoles as effective and comfortable in comparison to 19% of the users of the placebo insoles (P<0.05). The results of this study indicate a substantial improvement in the low back pain after the use of the true insoles. The average pain intensity according to the MILLION questionnaire before the use of the insoles was 5.46. However, after the use of the real insoles and the placebo insoles, the average pain intensity decreased to 3.96 and 5.11, respectively. The difference of the average pain intensity at the start of the study and after the use of the real insoles was significant: -1.49 (P=0.0001), whereas this difference after the use of the placebo insoles was not significant: -0.31 (P=0.1189). The reported severity of pain also decreased significantly: a level 5 pain and above was reported by 77% of the subjects at the start of the study. After the use of the real insoles only 37.9% of the subjects reported a similar degree of pain severity, and 50% of the subjects did so after the use of the placebo insoles (P< 0.05). We did not find a link between low back pain and other variables such as gender, age, number of offspring, work seniority, smoking, previous use of insoles and previous medication. This study demonstrates that the low back pain decreased significantly after the use of real insoles compared to placebo ones.

Adult↗

Developing a reliable Senior Walking Environmental Assessment Tool.

BACKGROUND: Research of the effects of the built environment on physical activity often excludes certain segments of the population. The senior population, one segment perhaps most influenced by the physical features of an environment, has been understudied. Developing reliable measures of the environment is important to increase our understanding of the environmental effects on physical activity among seniors. METHODS: A review of urban planning and health literature helped identify important concepts and theories that were used to inform the development of the Senior Walking Environmental Assessment Tool (SWEAT). Urban planning and health research professionals were consulted and provided feedback on the tool. A total of 355 neighborhood segments were assessed using SWEAT. Thirty-six neighborhood segments were assessed for inter-rater reliability. RESULTS: Overall, raters exhibited good-to-excellent agreement on most items included in SWEAT. Items assessing buildings and destinations were less reliable than other categories. CONCLUSIONS: The development of a reliable senior-specific environmental measurement of detailed street level environmental features that may influence walking among seniors is important to advance this research and engage communities to consider simple environmental changes that encourage walking among seniors.

Aged↗

Effects of neuromuscular training on the reaction time and electromechanical delay of the peroneus longus muscle.

OBJECTIVE: To examine the influence of a 6-week neuromuscular training program on the electromechanical delay and reaction time of the peroneus longus muscle. DESIGN: A 2 x 2 pre-post factorial design. SETTING: Human performance research center biomechanics laboratory. PARTICIPANTS: Thirty-six healthy, physically active, college-age subjects were recruited for this study and 26 completed it. There were 5 men and 8 women in the treatment group (mean age +/- standard deviation, 21.9+/-2.1 y; height, 173.7+/-11.1cm; weight, 67.4+/-17.8 kg) and 6 men and 7 women in the control group (age, 21.8+/-2.3 y; height, 173.7+/-11.9 cm; weight, 70.8+/-19.4 kg). Subjects were not currently experiencing any lower-extremity pathology and had no history of injuries requiring treatment to either lower extremity. INTERVENTIONS: Subjects in the treatment group completed a 6-week neuromuscular training program involving various therapeutic exercises. Subjects in the control group were asked to continue their normal physical activity during the 6-week period. MAIN OUTCOME MEASURES: The electromechanical delay of the peroneus longus was determined by the onset of force contribution after artificial activation, as measured by electromyographic and forceplate data. Reaction time was measured after a perturbation during walking. Data were analyzed using two 2 x 2 analyses of covariance (covariate pretest score). Group (treatment, control) and sex (male, female) were between-subject factors. RESULTS: Neuromuscular training caused a decrease in reaction time to perturbation during walking compared with controls (F=4.030, P=.029), while there was a trend toward an increase in electromechanical delay (F=4.227, P=.052). There was no significant difference between sexes or the interaction of sex and treatment in either reaction time or electromechanical delay. CONCLUSIONS: The 6-week training program significantly reduced reaction time of the peroneus longus muscle in healthy subjects. Neuromuscular training may have a beneficial effect on improving dynamic restraint during activity.

Adult↗

Prosthetic intervention effects on activity of lower-extremity amputees.

OBJECTIVE: To investigate the effect of prosthetic interventions on the functional mobility of lower-extremity amputees. DESIGN: Crossover with repeated measures. SETTING: Household and community environment. PARTICIPANTS: Twelve transtibial and 5 transfemoral amputees. INTERVENTIONS: For transtibial amputees, shock-absorbing versus rigid pylons. For transfemoral amputees, C-Leg versus Mauch SNS knees. MAIN OUTCOME MEASURES: Daily activity level (step count) and duration (minutes of activity). RESULTS: Pylon type had no effect on the daily activity level or duration of transtibial amputees. Knee type had no effect on the daily activity level or duration of transfemoral amputees. Transtibial amputees were more active on weekdays (3079+/-1515 steps/d) than weekends (2386+/-1225 steps/d) (P=.007). In general, lower-extremity amputees perform numerous short-duration bouts of activity (1-2 min) consisting of fewer than 17 steps/min, but activities of more than 15 minutes in duration were relatively rare (<1 per day). CONCLUSIONS: Intervention had no effect on amputee activity level and duration. Higher weekday activity levels of transtibial amputees suggest their vocational activities are more demanding than recreational activities. The fitting, alignment, and design of prosthetic components should be optimized for 1 to 2 minute bouts of activity consisting of only a few dozen steps.

Adult↗

The Oslo balloon angioplasty versus conservative treatment study (OBACT)--the 2-years results of a single centre, prospective, randomised study in patients with intermittent claudication.

OBJECTIVES: To compare the effect of optimal medical treatment only (OMT) with OMT combined with percutaneous transluminal angioplasty (OMT+PTA) in patients with intermittent claudication (IC). DESIGN: A single centre prospective, randomised study. Quality of life (QoL) was the primary outcome measure. Secondary measures were ankle-brachial-index (ABI), treadmill walking distances and mortality. METHODS: From a total of 434 patients considered for inclusion into the trial, only 56 patients with disabling IC fulfilled the inclusion criteria. The patients were randomised into treatment groups consisting of 28 patients each and followed for 2 years. ABI and treadmill walking distances were measured in addition to the visual analogue scale (VAS) for pain evaluation, and QoL assessment using the Short Form (SF-36 and Claudication Scale (CLAU-S). RESULTS: The demographic data in the 2 groups were almost identical. After 2 years of follow-up the ABI, the treadmill walking distances and the VAS were significant improved in the group treated with OMT+PTA, compared to the group treated with OMT only (p<0.01 for all). Furthermore, some variables from the QoL assessment also showed a significant improvement in favour of the OMT+PTA group (p<0.05 for all). CONCLUSION: The advantage of conducting a single centre study and adhering to very strict inclusion criteria was illustrated by the homogenous demographic data of the two groups. This partly outweighed the disadvantage of having included a relatively small number of patients. Early intervention with PTA in addition to OMT seems to have a generally more positive effect compared to OMT only, on haemodynamic, functional as well as QoL aspects during the first 2 years in patients with IC.

Aged↗

Ground reaction force and 3D biomechanical characteristics of walking in short-leg walkers.

Short-leg walking boots offer several advantages over traditional casts. However, their effects on ground reaction forces (GRF) and three-dimensional (3D) biomechanics are not fully understood. The purpose of the study was to examine 3D lower extremity kinematics and joint dynamics during walking in two different short-leg walking boots. Eleven (five females and six males) healthy subjects performed five level walking trials in each of three conditions: two testing boot conditions, Gait Walker (DeRoyal Industries, Inc.) and Equalizer (Royce Medical Co.), and one pair of laboratory shoes (Noveto, Adidas). A force platform and a 6-camera Vicon motion analysis system were used to collect GRFs and 3D kinematic data during the testing session. A one-way repeated measures analysis of variance (ANOVA) was used to evaluate selected kinematic, GRF, and joint kinetic variables (p<0.05). The results revealed that both short-leg walking boots were effective in minimizing ankle eversion and hip adduction. Neither walker increased the bimodal vertical GRF peaks typically observed in normal walking. However, they did impose a small initial peak (<1BW) earlier in the stance phase. The Gait Walker also exhibited a slightly increased vertical GRF during midstance. These characteristics may be related to the sole materials/design, the restriction of ankle movements, and/or the elevated heel heights of the tested walkers. Both walkers appeared to increase the demand on the knee extensors while they decreased the demand of the knee and hip abductors based on the joint kinetic results.

Adult↗

Travel path conditions dictate the manner in which individuals avoid collisions.

The ability to perceive the motion of approaching objects and to make appropriate adjustments to avoid collisions is an essential component of safe locomotion through the environment. No previous study has looked at actual behavioural responses in a realistic collision avoidance task. We investigated individuals' collision avoidance behaviour with an approaching object in order to understand the visual information used to accomplish the task. We found that when individuals were walking towards a goal without any restrictions, a change in travel path occurred at the same time, independent of the object's approach velocity. However, the lateral rate of change in the travel path was significantly slower for the slower approach velocity. We found that when a restriction was present along the travel path, individuals were exposed to the object's properties for longer and a change in travel path occurred later for slowest approaching velocities than for the fastest approaching velocities. The results suggest that individuals are capable of determining TTC from an approaching object during actual self-motion, but the motor parameter it modulates is different for different circumstances.

Adult↗

The effect of a concurrent task on the walking performance of preschool children.

Forty-eight children, aged 4-6 years, walked while performing or not performing an easy or difficult concurrent motor task (carrying a tray with or without marbles on it) or cognitive task (repeating a series of digits forwards or backwards). The temporal-distance gait parameters were measured using a GAITRite electronic walkway system. Dual-task costs were calculated as the difference between the children's walking performances with and without the concurrent task. Overall, walking alone was easier than walking while performing a concurrent task. A greater dual-task cost was observed when the concurrent task was difficult compared to when it was easy. However, this effect of difficulty was found for the motor task only. The results suggest that walking demands both the central processing capacity and the domain- and modality-specific processing resources in normal 4-6-year-old children.

Analysis of Variance↗

The influence of artificially increased trunk stiffness on the balance recovery after a trip.

Falls occur frequently in the growing population of elderly. Since trunk control is critical for maintaining balance, the higher trunk stiffness in elderly people compared to the general population has been associated with their increased fall-risk. Theoretically, trunk stiffness may be beneficial for balance recovery in walking, i.e. after a trip. A stiff joint may provide a torque that restricts the perturbation effects and thereby reduces the probability of a fall. The aim of this study was to test whether trunk stiffness impaired or assisted balance recovery after a trip during walking. An orthopedic corset was used to simulate trunk stiffness in 11 young male adults. Subjects walked over a platform, with or without the corset on, and were occasionally tripped over a hidden obstacle. Kinematics of the tripping reaction were measured. Initial trunk accelerations were significantly attenuated by the corset, which indicates a positive effect of the stiffening corset. However, no subsequent effects on peak trunk inclination and on the peak moment arm of gravity on the trunk were found. The pattern of trunk motion allowed ample time for triggered or voluntary muscle responses to be generated, before a substantial inclination occurred. It appears that such active responses were sufficient in the young subjects tested to obtain a similar net effect with or without the increased trunk stiffness induced by the corset.

Accidental Falls↗

Clinical outcomes of expiratory muscle training in severe COPD patients.

UNLABELLED: The most common symptoms in chronic obstructive pulmonary disease (COPD) patients are breathlessness and exercise limitation. Although both general and inspiratory muscle training have shown clinical benefits, the effects of specific expiratory muscle training remain controversial. OBJECTIVE: To investigate the effects of expiratory training on lung function, exercise tolerance, symptoms and health-related quality of life in severe COPD patients. METHODS: Sixteen patients (FEV(1), 28+/-8% pred.) were randomised to either expiratory muscle or sham training groups, both completing a 5-week programme (30 min sessions breathing through an expiratory threshold valve 3 times per week) (50% of their maximal expiratory pressure (MEP) vs. placebo, respectively). Lung function, exercise capacity (bicycle ergometry and walking test), and clinical outcomes (dyspnoea and quality of life (St. George Respiratory Questionnaire (SGRQ)) were evaluated both at baseline and following the training period. RESULTS: Although lung function remained roughly unchanged after training, exercise capacity, symptoms and quality of life significantly improved. The improvement in both walking distance and the SGRQ score significantly correlated with changes in MEP. CONCLUSION: Our results confirm that a short outpatient programme of expiratory training can improve symptoms and quality of life in severe COPD patients. These effects could be partially explained by changes in expiratory muscle strength.

Aged↗

The effect of bronchodilators and oxygen alone and in combination on self-paced exercise performance in stable COPD.

Both oxygen therapy and bronchodilators reduce exertional breathlessness and improve exercise tolerance in patients with stable chronic obstructive pulmonary disease (COPD). However their relative effectiveness and the value of their combined use on exercise performance has not been assessed. The effects of 5 mg of salbutamol plus 500 microg ipratropium bromide nebulisation followed by a 6-min walking test while breathing O(2) were studied in a randomised, single-blind, placebo controlled, crossover trial in 28 patients with severe or very severe COPD, breathless on exertion and with oxygen saturation < or = 89% at rest or on exercise. Bronchodilator reversibility was minimal. The 6-min walking distance increased from 356 (128)m to 377 (117)m after the bronchodilator (P<0.05), to 406 (109)m after supplementary oxygen but without bronchodilators (P 0.011 versus bronchodilators/air and 0.001 versus placebo/air), and to 430 (109)m after the combination of oxygen and the bronchodilators (P<0.0001 versus placebo/air and bronchodilators/air; P=0.014 versus placebo/oxygen). End-exercise dyspnea only fell significantly when oxygen and bronchodilator were combined. In severe or very severe COPD patients with relatively fixed airway obstruction bronchodilators enhance exercise performance obtained with oxygen. Clinically relevant improvement is possible when therapies with a different mechanism of action are combined.

Aged↗

Active transportation to school over 2 years in relation to weight status and physical activity.

OBJECTIVE: To prospectively examine potential benefits of active commuting to school on measures of weight status and physical activity in a sample of youth. RESEARCH METHODS AND PROCEDURES: A cohort of students from seven elementary schools was measured four times--in the fall and spring of fourth grade (N = 1083) and fifth grade (N = 924). Participants were classified as active (walking, biking, or skateboarding to school almost every day for baseline analyses or at least 2 d/wk for analyses of consistent active commuting) or non-active commuters to school. Accelerometers were used to measure physical activity. Height, weight, and skinfolds were objectively assessed. RESULTS: Boys who actively commuted to school had lower BMI (p < 0.01) and skinfolds (p < 0.05) than non-active commuters to school in the fourth grade. Active commuting to school over 2 years was not associated with BMI change or overweight status. DISCUSSION: Walking and cycling to school may contribute to preventing excessive weight gain, or leaner children may walk or cycle to school.

Analysis of Variance↗

Effects of the glycemic index of breakfast on metabolic responses to brisk walking in females.

OBJECTIVE: The aim of this study was to examine the metabolic responses during 1 h of brisk walking, 3 h after ingesting high glycemic index (HGI) and moderate glycemic index (MGI) breakfasts. DESIGN AND SUBJECTS: Six females completed three treadmill walking trials (approximately 50% VO2 max), separated by at least 1 month. Three hours before walking, they ingested either water or a HGI or MGI breakfast. The MGI breakfast consisted of a mixture of an HGI breakfast cereal and low GI carbohydrate (CHO) foods. The GI values of the HGI and MGI meals were 77 and 51, respectively. SETTING: The study took place in the School of Sport and Exercise Sciences at Loughborough University, Loughborough, UK. RESULTS: In the HGI and MGI trials, plasma glucose and serum insulin concentrations peaked 15 min into the postprandial period. At the onset of exercise, plasma insulin concentrations were twofold higher in the HGI (31.5+/-7.7 microl U l(-1)) than in the MGI trial (15.2+/-1.9 microl U l(-1)) (P<0.05). However, there were no differences in substrate utilization between the two CHO trials. CONCLUSION: These results suggest that although the addition of LGI CHO foods to an HGI breakfast cereal reduces the overall GI of the meal, the metabolic response to exercise is similar to that following a breakfast comprised entirely of HGI foods.

Adult↗