Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Random walk”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,495 records · Page 83Linked to original sources
PubMed2006

A randomized controlled trial of supervised versus unsupervised exercise programs for ambulatory stroke survivors.

BACKGROUND AND PURPOSE: Little is known about the relative efficacy of supervised versus unsupervised community exercise programs for stroke survivors. This study compared the effectiveness of a 10-week supervised strengthening and conditioning program (supervised) with a 1-week supervised instruction program followed by a 9-week unsupervised home program (unsupervised) and evaluated retention of changes at 6 months and 1 year after program completion. METHODS: Seventy-two subjects retained at baseline (27 women, 45 men; mean+/-SD age, 64.6+/-11.8 years) were randomly allocated to receive the supervised or unsupervised program. The primary outcome was walking speed over 6 minutes, and secondary outcome measures were Human Activity Profile, Medical Outcome Study 36-Item Short-Form survey (SF-36), Physiological Cost Index, and lower extremity muscle strength. RESULTS: The 6-minute walking speed increased significantly in both groups and remained significantly improved by 1 year. The Human Activity Profile demonstrated an increasing trend only in the supervised group that was significant by 1 year. The SF-36 Physical Component summary score increased significantly in the supervised group and remained improved by 1 year; the unsupervised group showed significant improvement at 1 year. Women made greater gains in supervised programs, but men made greater gains in unsupervised programs. CONCLUSIONS: Supervised exercise programs and unsupervised programs after initial supervised instruction were both associated with physical benefits that were retained for 1 year, although supervised programs showed trends to greater improvements in self-reported gains. Gender differences require further research.

Activities of Daily Living↗
PubMed1986

Comparison of isocapnic hyperventilation and walking exercise training at home in pulmonary rehabilitation.

Eighteen COPD patients enrolled in a comprehensive, multidisciplinary pulmonary rehabilitation program were randomly assigned to perform either: 1) walking, or 2) ventilatory muscle exercise training (VMT) using a prototype, portable device for isocapnic hyperventilation training. Both groups performed exercise training at home. Twelve patients completed the study and follow-up evaluation (five VMT, seven walkers). Pulmonary function did not change in either group. For the VMT patients, there were modest increases in ventilatory muscle endurance and exercise performance. VO2max and VEmax increased significantly. For the walkers, only walking endurance time increased significantly. These results indicate that isocapnic hyperventilation exercise training can be performed successfully by COPD patients in an unsupervised home setting and can lead to improvement in both ventilatory muscle endurance and exercise performance. Walking exercise training did not improve ventilatory muscle endurance.

Aged↗
PubMed2003

Exercise self-efficacy in older adults: social, affective, and behavioral influences.

A 6-month randomized controlled trial examined the effect of walking and stretching/toning activity on changes in self-efficacy to overcome barriers and engage in incremental periods of activity in older, formerly sedentary adults (N = 174, M age = 65.5 years). Additionally, we were interested in the extent to which social, affective, and behavioral influences contributed to self-efficacy at the end of the 6-month program. Multiple sample latent growth curve analyses revealed a nonsignificant curvilinear growth pattern for barriers efficacy with increases in efficacy occurring from baseline to 2 months and then declining at 4 and 6 months. In the case of efficacy related to continued activity participation, there was a significant growth pattern demonstrating declines in efficacy over the 4 time points. Structural modeling analyses revealed significant direct effects of physical activity, affect experienced during activity, and exercise social support on both types of self-efficacy. These relationships were not significantly different between modes of activity. The findings are discussed in terms of the need to target sources of efficacy information prior to program end and the implications that such an approach might have for long-term maintenance of physical activity in older adults.

Affect↗
PubMedDate not supplied

The role of biomechanical shoe orthoses in tibial stress fracture prevention.

BACKGROUND: Biomechanical orthoses have been shown to lower stress fracture incidence in infantry recruits. However, these results may not be applicable to running athletes. HYPOTHESIS: Training in either running shoes or military boots with custom biomechanical shoe orthoses lessens tibial bone strains and strain rates during walking and running. STUDY DESIGN: Randomized controlled laboratory study. METHODS: In vivo strain measurements were made in nine subjects to determine whether the use of biomechanical orthoses lowers tibial strains during both walking and running and whether such lowering depends on the type of shoe worn. Measurements were made during treadmill walking at 5 km/hr and then during serial 2-km treadmill runs at 13 km/hr with running shoes, with and without the orthoses, and during serial 1-km runs with army boots, with and without the orthoses. RESULTS: When soft or semirigid biomechanical orthoses were worn with boots, the tibial peak-to-peak strains were significantly lowered. Soft orthoses also significantly lowered the tension and compression strain rates when worn with boots. During running, semirigid orthoses significantly increased the compression and tension strain rates when worn with boots. CONCLUSIONS: The use of biomechanical orthoses may be warranted for tibial stress fracture prevention during training in which boots are worn and that mostly involves walking, but they are not warranted for activities that primarily involve running or are performed in running shoes.

Adult↗
PubMed2000

Exercise training in intermittent claudication.

BACKGROUND: Peripheral arterial occlusive disease (PAOD) at II stage results in a moderate to severe impairment in walking ability. Aim of this study, controlled and randomized, was to evaluate the efficacy of an intensive 4 weeks exercise training in PAOD followed by a six-month period and to analyse the risk factors for atherosclerosis and the site of the lesion for possible predictors of result outcome. METHODS: Patients with PAOD were included in the study (ankle/arm ratio < or = 0.7 and < or = 0.5 after exercise) with initial claudication distance (ICD) < or = 200 m and absolute claudication distance (ACD) < or = 500 m evaluated on a constant-load treadmill test (3 km/hr, 0% slope). Forty patients were randomized (all with antiplatelet therapy): 20 to a supervised walking exercise (mean ICD 121.8 m, ACD 289.7 m) and 20 to a non exercising control group (ICD 111.6 m, ACD 230.1 m). Both groups were tested at 4 weeks (T1) and 6 months (T2). Training group was enrolled in a 4-week supervised training program. RESULTS: In the training group 10% of patients became asymptomatic (>1000 m). At T1 ICD increased 141% (p<0.001) and ACD was with low-pain-claudication >1000 m in 50%, at T2 ICD was 200% (p<0.05) with 70% of asymptomatic for ICD and ACD. Control group has a no significant increase of ICD and ACD at T1 and T2. Only arterial hypertension and intermittent claudication severity emerged as negative predictive factors for the results of training. CONCLUSIONS: Vascular training produces a significant and lasting improvement in walking distance in PAOD.

Aged↗
PubMed2003

The effect of epidural test dose on motor function after a combined spinal-epidural technique for labor analgesia.

UNLABELLED: Labor analgesia initiated with intrathecal bupivacaine and fentanyl, without a local anesthetic epidural test dose, provides effective analgesia and allows ambulation. In this study, we sought to determine the effect of a lidocaine-epinephrine test dose administered immediately after the initiation of combined spinal-epidural (CSE) analgesia with bupivacaine 2.5 mg and fentanyl 25 micro g on parturients' hemodynamic stability, posterior column function, motor strength, and subjective ability to walk. Parturients (n = 153) were randomized to receive either 3 mL of epidural saline or lidocaine 1.5% with epinephrine 1:200,000. Hemodynamic variables, proprioception, straight leg raise, and the modified Bromage score were analyzed in 110 parturients who completed the study protocol and were not different between groups. Vibratory sense, the ability to perform a partial deep knee bend and to step up on a stool, and the subjective ability to walk were impaired in a larger number of parturients in the lidocaine-epinephrine group at 30 min (P < 0.05). At 60 min, there were no differences between the groups except that fewer parturients in the lidocaine-epinephrine group could step up on a stool. The straight leg raise against resistance and the modified Bromage scale did not correlate well with other tests of motor strength (Spearman's rho, 0.273-0.405). These data suggest that the test dose should be avoided immediately after initiation of CSE analgesia when early ambulation is desired. IMPLICATIONS: A lidocaine-epinephrine epidural test dose (3 mL of lidocaine 1.5% with epinephrine 1:200,000), injected immediately after the initiation of combined spinal-epidural labor analgesia with bupivacaine 2.5 mg and fentanyl 25 microg, may interfere with the ability to perform simple tests of motor function and ambulation.

Adult↗
PubMed1993

Effect of a walking program on gait characteristics in patients with osteoarthritis.

This paper reports the results of a study of the gait of 102 patients with osteoarthritis of the knee. Functional status was measured by a 6-min test of walking distance; the stride characteristics associated with the walk test were assessed. Stride characteristics were measured by a Stride Analyzer. Patients were randomized to an 8-week educational and walking program (the intervention group) or to a weekly telephone survey (the control group). The intervention group patients had a 15% increase in walking distance (P < 0.0001) and increases of 9.1% in stride length at free walking speeds (P < 0.007) and 17% in stride length at fast walking speeds (P < 0.01) compared to the control group. The results of this study have shown that the walking and educational program was effective in improving gait function in patients with osteoarthritis of the knee.

Adult↗
PubMed1997

Path integration by swimming rats

Path integration is a process that enables a moving animal to memorize the location of the starting point of its outward path relative to its current position by continuously processing motion-related information collected en route (route-based information). There has been no evidence, however, that path integration could be used by a swimming animal, even in aquatic or amphibious species. I conducted water maze experiments to test whether rats, Rattus norvegicuscan rely on path integration while swimming, in order to return to a hidden escape platform after circular outward paths ranging from 60&deg; to 300&deg;. Rats proved able to perform the task in a few days. No systematic errors in the distribution of return directions could be observed. In contrast, there was a fairly large random error (about 55&deg;), which, surprisingly, did not depend on the outward path length. Comparison with walking rats could not be made because of the lack of published data. However, results for walking hamsters, Mesocricetus auratusshowed that their random errors are slightly smaller than those made by swimming rats. Such large errors are likely to prevent rats as well as hamsters (and presumably any swimming or walking mammal) from using path integration over long outward paths.

Journal Article↗
PubMed1990

Application of an efficient strategy with a phage lambda vector for constructing a physical map of the amyloplast genome of sycamore (Acer pseudoplatanus).

Amyloplasts were isolated from a heterotrophic culture cell line of a woody plant, sycamore (Acer pseudoplatanus), and their DNA was purified. Conventional procedures for making a physical map were not easily applicable to the amyloplast DNA, since the yield of DNA was too low and the presence of repeated sequences interfered with the analysis. Therefore, the pieces of amyloplast DNA starting with a few micrograms of DNA were cloned in the lambda Fix vector, which is a derivative of lambda EMBL vectors improved for efficient cloning and gene walking. Cloned DNA fragments were randomly picked, mapped for restriction endonuclease sites by a refined procedure, and combined by overlapping their physical maps. The DNA library was also subjected to screening by gene walking using promoters recognized by T3 and T7 RNA polymerases in the vector to fill the gaps between sequences determined by overlapping the physical maps. In this way, we constructed the entire DNA library and the complete physical map of the amyloplast DNA. The sycamore amyloplast genome was composed of 141.7-kbp nucleotides with the same gene arrangement as that of tobacco chloroplasts.

Bacteriophage lambda↗
PubMed2005

A pilot study of L-arginine supplementation on functional capacity in peripheral arterial disease.

Peripheral arterial disease (PAD) impairs walking capacity and is often associated with a profound endothelial vasodilator dysfunction, characterized by reduced bioactivity and/or synthesis of endothelium-derived nitric oxide (NO). Previous studies have suggested that dietary supplementation of L-arginine, the precursor of NO, improves endothelium-dependent vasodilation, limb blood flow and walking distance. However, these studies have been small, and have used large intravenous doses of L-arginine. The optimal dose of L-arginine has not been determined. Accordingly, this pilot study was conducted to establish the lowest effective oral dose of L-arginine to improve walking distance in preparation for the definitive study. Patients with PAD and intermittent claudication (n = 80) participated in this study. Eligibility criteria included: (1) ankle-brachial index (ABI) at rest < or = 0.90; (2) post-exercise reduction in ABI > or = 25%; and (3) difference in absolute claudication distance of < or = 25% between two consecutive treadmill tests. Treadmill testing was performed using the Skinner-Gardner protocol and community-based walking was assessed using the walking impairment questionnaire. Patients were randomly assigned to oral doses of 0, 3, 6 or 9 g of L-arginine daily in three divided doses for 12 weeks. Treadmill testing was performed prior to administration of the study drug and again after 12 weeks of treatment. The study drug was well tolerated, with no significant adverse effects of L-arginine therapy. The safety laboratory studies were unremarkable, except for a statistically significant reduction in hematocrit in the L-arginine-treated groups. There was no significant difference observed in absolute claudication distance between the groups. However, a trend was observed for a greater increase in walking distance in the group treated with 3 g L-arginine daily, and there was a trend for an improvement in walking speed in patients treated with L-arginine. This pilot study provided data for safety, for power calculation and for dosing for the larger definitive trial that is now underway.

Administration, Oral↗
PubMed2002

The effects of exercise on children with attention-deficit hyperactivity disorder.

PURPOSE: The effects of exercise on children with attention-deficit hyperactivity disorder (ADHD) were evaluated by studying the rate of spontaneous eye blinks, the acoustic startle eye blink response (ASER), and motor impersistence among 8- to 12-yr-old children (10 boys and 8 girls) meeting DSM-III-R criteria for ADHD. METHODS: Children ceased methylphenidate medication 24 h before and during each of three daily conditions separated by 24-48 h. After a maximal treadmill walking test to determine cardiorespiratory fitness (VO(2peak)), each child was randomly assigned to counterbalanced conditions of treadmill walking at an intensity of 65-75% VO(2peak) or quiet rest. Responses were compared with a group of control participants (11 boys and 14 girls) equated with the ADHD group on several key variables. RESULTS: Boys with ADHD had increased spontaneous blink rate, decreased ASER latency, and decreased motor impersistence after maximal exercise. Girls with ADHD had increased ASER amplitude and decreased ASER latency after submaximal exercise. CONCLUSIONS: The findings suggest an interaction between sex and exercise intensity that is not explained by physical fitness, activity history, or selected personality attributes. The clinical meaning of the eye blink results is not clear, as improvements in motor impersistence occurred only for boys after maximal exercise. Nonetheless, these preliminary findings are sufficiently positive to encourage additional study to determine whether a session of vigorous exercise has efficacy as a dopaminergic adjuvant in the management of behavioral features of ADHD.

Acoustic Stimulation↗
PubMed1994

Superiority of treadmill walking exercise versus strength training for patients with peripheral arterial disease. Implications for the mechanism of the training response.

BACKGROUND: In patients with intermittent claudication, a supervised walking exercise program increases peak exercise performance and community-based functional status. Patients with peripheral arterial disease also have muscle weakness in the affected extremity that may contribute to the walking impairment. However, the potential benefits of training modalities other than walking exercise, such as strength training, have not been critically evaluated in this patient population. The present study tested the hypothesis that a strength training program would be as effective as treadmill walking exercise and that combinations of strengthening and walking exercise would be more effective than either alone in improving exercise performance. METHODS AND RESULTS: Twenty-nine patients with disabling claudication were randomized to 12 weeks of supervised walking exercise on a treadmill (3 h/wk at a work intensity sufficient to produce claudication), strength training (3 h/wk of resistive training of five muscle groups of each leg), or a nonexercising control group. Graded treadmill testing was performed to maximally tolerated claudication pain to define changes in peak exercise performance. After 12 weeks, patients in the treadmill training program had a 74 +/- 58% increase in peak walking time as well as improvements in peak oxygen consumption (VO2) and the onset of claudication pain. Patients in the strength-trained group had a 36 +/- 48% increase in peak walking time but no change in peak VO2 or claudication onset time. Control subjects had no changes in any of these measures over the 12-week period. After the first 12 weeks, patients in the initial walking exercise group continued for 12 more weeks of supervised treadmill training. This resulted in an additional 49 +/- 53% increase in peak walking time (total of 128 +/- 99% increase over the 24 weeks). After the initial 12 weeks, patients in the strength-trained group began 12 weeks of supervised treadmill training, and patients in the control group participated in a 12-week combined program of strengthening and treadmill walking exercise. The combined strength and treadmill training program and treadmill training after 12 weeks of strength training resulted in increases in peak exercise performance similar to those observed with 12 weeks of treadmill training alone. CONCLUSIONS: A supervised treadmill walking exercise program is an effective means to improve exercise performance in patients with intermittent claudication, with continued improvement over 24 weeks of training. In contrast, 12 weeks of strength training was less effective than 12 weeks of supervised treadmill walking exercise. Finally, strength training, whether sequential or concomitant, did not augment the response to a walking exercise program.

Aged↗
PubMed2003

Increased ventilation with NiIPPV does not necessarily improve exercise capacity in COPD.

Evidence that noninvasive intermittent positive-pressure ventilation (NiIPPV) improves exercise capacity in chronic obstructive pulmonary disease (COPD) is limited. The effectiveness of different ventilators in this setting has not been studied. Three bilevel pressure support ventilators (Bipap S/T 30, Nippy2 and Vpap II ST), applied via a mouthpiece, were compared during submaximal treadmill exercise in eight subjects with COPD. Subjects walked to exhaustion with each of the ventilators and while breathing through the mouthpiece alone, in random order. In addition, four unencumbered walks were performed. The unencumbered distance (mean +/- SD) walked was 259 +/- 123 m. With the mouth-piece alone this decreased to 211 +/- 96 m and fell further to 145 +/- 76 m with NiIPPV. There was no difference between the brands of ventilator. At the break-point of exercise, significant increases were seen in tidal volume and minute ventilation in the ventilator walks compared with the mouthpiece alone. Noninvasive intermittent positive-pressure ventilation increased ventilation but did not improve exercise capacity in the subjects in this study. No significant differences were seen between the ventilators. The effectiveness of this technique and the optimal method of assistance require further clarification.

Aged↗
PubMed2006

Six minute walk distance is greater when performed in a group than alone.

OBJECTIVE: To investigate whether the distance covered in the six minute walk test was affected by walking with a group of others in comparison with performing the test alone. METHODS: Eight healthy men (mean (SD) age 21.0 (0.9) years) and eight healthy women (mean (SD) age 20.8 (2.0) years) performed in random order two six minute walk tests either alone or in a group of four on two separate occasions one week apart. RESULTS: Distance covered increased significantly from a mean of 653 (61) m in the individual male tests to 735 (79) m in the male group tests (p<0.05), and 616 (75) m in the individual female tests to 701 (54) m in the female group tests (p<0.01). The men increased the distance walked in six minutes by 12.5% and the women by 13.7% when they performed the test as a group. CONCLUSION: Performing the six minute walk test in a group facilitates its execution.

Adult↗
PubMed2006

Effect of treadmill and overground walking on function and attitudes in older adults.

PURPOSE: The purpose of this study was to determine whether treadmill walking, as a mode of physical activity for older adults, was comparable with overground walking when considering 1) spatiotemporal gait characteristics (walking velocity, stride length, and stride rate) at a preferred velocity and a prescribed intensity typical of many exercise prescriptions (i.e., RPE of 13); and 2) the effects on physical function (short physical performance battery (SPPB), lateral mobility, 400-m walk) and participants' attitude towards training and level of enjoyment. METHODS: Gait characteristics were measured at each participant's preferred and RPE 13 velocity during treadmill and overground walking (N=23, 74+/-4 yr). Participants were then randomized to either a treadmill or overground progressive intensity and duration walking program of 18 sessions. RESULTS: Both the preferred and RPE 13 walking velocities were significantly slower on the treadmill compared with overground (t(22)=-10.87, P<0.001 and t(22)=-8.54, P<0.001, respectively), as a result of significantly shorter stride lengths and slower stride rates. After training, there were no differences between the groups for RPE 13 velocity, SPPB or lateral mobility. However, following the intervention, the overground group completed the 400-m walk faster (F(1,15)=6.06, P<0.05), had a more favorable attitude towards training, and expressed a more favorable level of enjoyment about the training program than the treadmill group (F(1,16)=7.5; P<0.05). CONCLUSION: An overground walking program appears to offer some advantages over a treadmill walking program in older adults. Using RPE alone to regulate intensity may reduce the benefits of a treadmill walking program in older adults.

Aged↗
PubMed2005

Physical activity and executive functions in the elderly with mild cognitive impairment.

The primary goal of the present study was to examine whether in the elderly with mild cognitive impairment (MCI), the effect of physical activity measured directly following treatment, was reflected in an improvement in cognitive functioning in general or in executive functions (EF) in particular. Secondly, this study aimed to compare the effectiveness of two types of intervention, with varying intensities: walking and hand/face exercises. Forty-three frail, advanced elderly subjects (mean age: 86) with MCI were randomly divided into three groups, namely, a walking group (n=15), a group performing hand and face exercises (n=13), and a control group (n=15). All subjects received individual treatment for 30 minutes a day, three times a week, for a period of six weeks. A neuropsychological test battery, administered directly after cessation of treatment, assessed cognitive functioning. The results show that although a (nearly) significant improvement in tasks appealing to EF was observed in both the walking group and the hand/face group compared to the control group, the results should be interpreted with caution. Firm conclusions about the effectiveness of mild physical activity on EF in the oldest old can only be drawn after studies with larger number of subjects.

Activities of Daily Living↗
PubMed2007

Repetitive locomotor training and physiotherapy improve walking and basic activities of daily living after stroke: a single-blind, randomized multicentre trial (DEutsche GAngtrainerStudie, DEGAS).

OBJECTIVE: To evaluate the effect of repetitive locomotor training on an electromechanical gait trainer plus physiotherapy in subacute stroke patients. DESIGN: Randomized controlled trial. SETTING: Four German neurological rehabilitation centres. SUBJECTS: One hundred and fifty-five non-ambulatory patients (first-time stroke <60 days). INTERVENTION: Group A received 20 min locomotor training and 25 min physiotherapy; group B had 45 min physiotherapy every week day for four weeks. MAIN OUTCOME MEASURES: Primary variables were gait ability (Functional Ambulation Category, 0-5) and the Barthel Index (0-100), blindly assessed at study onset, end, and six months later for follow-up. Responders to the therapy had to become ambulatory (Functional Ambulation Category 4 or 5) or reach a Barthel Index of > or = 75. Secondary variables were walking velocity, endurance, mobility and leg power. RESULTS: The intention-to-treat analysis revealed that significantly greater number of patients in group A could walk independently: 41 of 77 versus 17 of 78 in group B (P B < 0.0001) at treatment end. Also, significantly more group A patients had reached a Barthel Index > or = 75: 44 of 77 versus 21 of 78 (P B < 0.0001). At six-month follow-up, the superior gait ability in group A persisted (54 of 77 versus 28 of 78, P B < 0.0001), while the Barthel Index responder rate did not differ. For all secondary variables, group A patients had improved significantly more (P B < 0.0001) during the treatment period, but not during follow-up. CONCLUSIONS: Intensive locomotor training plus physiotherapy resulted in a significantly better gait ability and daily living competence in subacute stroke patients compared with physiotherapy alone.

Activities of Daily Living↗