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At least 1,531 records · Page 85Linked to original sources
PubMed2005

Effect of treadmill testing and exercise training on self-efficacy in patients with heart failure.

BACKGROUND: Self-efficacy is a person's confidence in being able to successfully perform a specific activity or behavior. Self-efficacy has been shown to influence exercise capacity in patients post myocardial infarction, but has not been fully explored in patients with heart failure (HF). This study examined the impact of performance of a single treadmill exercise test and participation in a 3-month program of walking and resistance exercise on self-efficacy in HF patients. METHODS: 24 patients were randomized to either a home-based walking and resistance exercise program or usual care for 3 months. Prior to enrollment into the exercise program all participants performed a single treadmill exercise test with respiratory gas analysis. Self-efficacy questionnaires were completed at 3 time points, 1) prior to performance of an exercise treadmill test; 2) immediately after completing an exercise test; and 3) at the end of a 3-month exercise program. RESULTS: Self-efficacy for walking (p=0.07), climbing (p=0.17), lifting (p=0.73) and general activity (p=0.15) did not improve after performance of a single treadmill exercise test and usual care. However, self-efficacy for walking increased after 3 months of a walking and resistance exercise program. (p=0.04). CONCLUSIONS: The findings from this study suggest that in patients with stable mild to moderate heart failure, self-efficacy is improved with participation in a home-based walking and endurance exercise program. Self-efficacy is not enhanced by performance of a single treadmill exercise test and usual care.

Adult↗
PubMedDate not supplied

Gait efficiency using the C-Leg.

Microprocessor-controlled prosthetic knees are claimed to improve gait efficiency in transfemoral (TF) amputees. This hypothesis was tested in a prospective randomized crossover trial that compared the Mauch SNS knee and the C-Leg microprocessor-controlled knee in eight TF amputees. The subjects were given a 3-month acclimation period in each knee. Then, their net oxygen cost (mL/kg/m) was measured while they walked overground at four speeds in random order: 0.8 m/s, 1.0 m/s, 1.3 m/s, and self-selected walking speed (SSWS). The C-Leg caused small reductions in net oxygen cost that were not statistically significant compared with the Mauch SNS at any of the walking speeds (p > 0.190). Subjects chose higher SSWSs with the C-Leg compared with the Mauch SNS (mean +/- standard deviation = 1.31 +/- 0.12 m/s vs 1.21 +/- 0.10 m/s, respectively, p = 0.046) but did not incur higher oxygen costs (p = 0.270), which suggests greater efficiency only at their SSWS.

Adult↗
PubMed2006

Monitoring activity in individuals with Parkinson disease: a validity study.

This study was conducted to investigate the validity of an Activity Monitor (AM) recording functional activities in individuals with Parkinson disease (PD). A series of tasks were performed in both a fixed and a random manner by 11 participants with PD (H & Y 2-3; age range 40-79 years). Participants, wearing an AM, were recorded for video analysis (VA). The strength of association (rs) between the AM and VA for duration of time in body positions, walking, and bicycling across both fixed and random modules ranged from 0.63 to 0.98, however, the AM reported significantly greater time spent in body positions in both modules. Kappa statistics (K) between the AM and VA were the highest for transitions in the fixed module with Ks ranging from 0.74 to 1.0. During the random module, the agreement between the AM and VA was lowest for transitions between sitting and standing. In general, the Ks were low for activities lasting less than 5 seconds. The data collected in the study support the conclusion that the AM accurately evaluated the duration of time spent in body positions, the number of transitions between body positions, and the duration of time spent walking for activities lasting longer than 5 seconds in individuals with PD.

Activities of Daily Living↗
PubMed1997

Self-paced resistance training and walking exercise in community-dwelling older adults: effects on neuromotor performance.

BACKGROUND: Resistance-training intervention studies have demonstrated meaningful health benefits in older adults; however, most have used exercises performed at specific intensities on expensive equipment, which limit their widespread applicability. We tested whether two self-paced, less expensive exercise protocols could be effective and safe for modifying neuromotor performance and functional capacity in community-dwelling adults 65-95 years of age. METHODS: One hundred and thirty-one subjects were randomized to a novel resistance training, walking, or control group. Subjects determined their level of resistance or walking intensity (self-paced) on a session-by-session basis. Muscle strength, balance, reaction time, stair climbing speed, and a timed pen pickup task were measured before and after the intervention period. Exercisers met three times per week for 10 months. RESULTS: Significant improvements in tandem stance and single-legged stance with eyes open times and stair climbing speed were seen in both exercise groups. In addition, resistance trainers improved their muscle strength and ability to pick up an object from the floor and reduced the number of missteps taken during tandem walking, and walkers reduced tandem walking time. Controls showed no significant improvement in any variable. CONCLUSIONS: The two self-paced exercise protocols were effective at improving neuromotor performance and functional capacity in the study sample and show promise as a safe, effective, cost-efficient, acceptable exercise model for primary and secondary prevention in the general population of community-dwelling older adults.

Aged↗
PubMedDate not supplied

The evolution of walking-related outcomes over the first 12 weeks of rehabilitation for incomplete traumatic spinal cord injury: the multicenter randomized Spinal Cord Injury Locomotor Trial.

BACKGROUND: The Spinal Cord Injury Locomotor Trial (SCILT) compared 12 weeks of step training with body weight support on a treadmill (BWSTT) that included overground practice to a defined but more conventional overground mobility intervention (CONT) in patients with incomplete traumatic SCI within 8 weeks of onset. No previous studies have reported walking-related outcomes during rehabilitation. METHODS: This single-blinded, randomized trial entered 107 American Spinal Injury Association (ASIA) C and D patients and 38 ASIA B patients with lesions between C5 and L3 who were unable to walk on admission for rehabilitation. The Functional Independence Measure (FIM-L) for walking, 15-m walking speed, and lower extremity motor score (LEMS) were collected every 2 weeks. RESULTS: No significant differences were found at entry and during the treatment phase (12-week mean FIM-L = 5, velocity = 0.8 m/s, LEMS = 35, distance walked in 6 min = 250 m). Combining the 2 arms, a FIM-L >or= 4 was achieved in < 10% of ASIA B patients, 92% of ASIA C patients, and all of ASIA D patients. Walking speed of >or= 0.6 m/s correlated with a LEMS near 40 or higher. CONCLUSIONS: Few ASIA B and most ASIA C and D patients achieved functional walking ability by the end of 12 weeks of BWSTT and CONT, consistent with the primary outcome data at 6 months. Walking-related measures assessed at 2-week intervals reveal that time after SCI is an important variable for entering patients into a trial with mobility outcomes. By about 6 weeks after entry, most patients who will recover have improved their FIM-L to >3 and are improving in walking speed. Future trials may reduce the number needed to treat by entering patients with FIM-L < 4 at > 8 weeks after onset if still graded ASIA B and at > 12 weeks if still ASIA C.

Adult↗
PubMed2003

Atriobiventricular pacing improves exercise capacity in patients with heart failure and intraventricular conduction delay.

OBJECTIVES: We sought to assess the efficacy of biventricular pacing with respect to both peak and submaximal measures of exercise in patients with New York Heart Association class III heart failure (HF) and intraventricular conduction delay in a randomized, blinded study. BACKGROUND: Submaximal and maximal changes in exercise capacity need evaluating in this patient population with this novel therapy. METHODS: Graded exercise and 6-min walk tests were performed in patients randomized to three months each of active (atrio-biventricular) and inactive pacing. Minute ventilation (VE), oxygen uptake (VO(2)), ventilated carbon dioxide (VCO(2)) and heart rate were measured in patients achieving a respiratory quotient >1 (n = 30). Oxygen pulse, anaerobic threshold (AT) and ventilatory efficiency (VE/VCO(2)) were calculated. RESULTS: Active biventricular pacing increased peak VO(2) (15.8 +/- 4.3 vs. 14.4 +/- 4.6 ml/kg/min, p = 0.02), exercise time (501 +/- 223 s vs. 437 +/- 233 s, p < 0.001) and oxygen pulse (9.3 +/- 2.8 vs. 8.1 +/- 3.1 ml/beat, p < 0.01) compared with inactive pacing. The submaximal measures of exercise capacity significantly increased with active pacing: AT (11.2 +/- 4.1 ml/kg/min vs. 9.5 +/- 2.3 ml/kg/min, p = 0.02) and 6-min walk (414 +/- 94 m vs. 359 +/- 94 m, p = 0.001). Minute ventilation/ventilated carbon dioxide improved (32 +/- 9 vs. 36 +/- 11, p = 0.03) with normalization of the VE/VCO(2) slope in 59% of patients (chi-square test, p = 0.002) with active pacing. CONCLUSIONS: Biventricular pacing may improve maximal and submaximal exercise capacity in patients with advanced HF and intraventricular conduction delay.

Adult↗
PubMed2002

Effect of cilostazol on treadmill walking, community-based walking ability, and health-related quality of life in patients with intermittent claudication due to peripheral arterial disease: meta-analysis of six randomized controlled trials.

OBJECTIVES: To assess whether cilostazol, a phosphodiesterase III inhibitor, improves treadmill and community-based walking ability and health-related quality of life (HQL) in patients with intermittent claudication resulting from peripheral arterial disease (PAD). DESIGN: Retrospective meta-analysis of data pooled from six Phase 3, multicenter, double-blind, placebo-controlled, parallel-group, randomized studies. SETTING: Patients were recruited from outpatient ambulatory medical care facilities. PARTICIPANTS: Patients' (n = 1,751) mean age +/- standard deviation was 65 +/- 9, and they had a history of PAD for 6 months or longer and an ankle brachial index (ABI) of 0.90 or less. INTERVENTION: Cilostazol 50 mg bid or 100 mg bid for 12, 16, or 24 weeks. MEASUREMENTS: ABI; maximal walking distance (MWD); pain-free walking distance on a graded and constant-load treadmill; and HQL, measured using the Walking Impairment Questionnaire (WIQ) and the Medical Outcomes Study Short Form-36 (SF-36). RESULTS: Maximal treadmill walking distance improved more in both cilostazol groups than in the placebo group (both P <.0001). WIQ and SF-36 physical summary scores improved significantly more with cilostazol than with placebo (for instance, WIQ distance score, P <.0001 and SF-36 physical summary score, P <.0001, comparing persons taking cilostazol with controls). Improved MWD correlated with improvements in WIQ (correlation with distance score, r = 0.34, P <.0001) and SF-36 physical summary scores (r = 0.29, P <.0001). CONCLUSIONS: Treatment with cilostazol was associated with greater improvements in community-based walking ability and HQL in patients with intermittent claudication than treatment with placebo. These improvements correlated with increased MWD. This analysis of effects of cilostazol on improving walking ability in persons with claudication is the first cilostazol study focused on community-based measures of functional status and HQL. Questionnaires assessing walking ability and HQL provide important patient-based information about clinical outcomes of claudication therapy.

Aged↗
PubMed2006

A randomised, controlled study on the effects of a short-term endurance training programme in patients with major depression.

OBJECTIVE: To evaluate the short-term effects of exercise in patients with major depression. DESIGN: Prospective, randomised, controlled study. SETTING: A university hospital. PATIENTS: A consecutive series of 38 inpatients with a major depression episode undergoing standard clinical antidepressant drug treatment. INTERVENTIONS: Patients were randomly assigned to an exercise (walking, n = 20) or placebo (low-intensity stretching and relaxation exercises, n = 18) group. Training was carried out for 10 days. MAIN OUTCOME MEASUREMENTS: Severity of depression assessed with the Bech-Rafaelsen Melancholy Scale (BRMS) and the Center for Epidemiologic Studies Depression scale (CES-D). RESULTS: After 10 days, reduction of depression scores in the exercise group was significantly larger than in the placebo group (BRMS: 36% v 18%; CES-D: 41% v 21%; p for both = 0.01); the proportion of patients with a clinical response (reduction in the BRMS scores by more than six points) was also larger for the exercise group (65% v 22%, p<0.01). CONCLUSIONS: Endurance exercise may help to achieve substantial improvement in the mood of selected patients with major depression in a short time.

Adult↗
PubMed1994

Influence of ondansetron on thermoregulation during exercise in the heat wearing combat clothing.

Ondansetron is a selective serotonin antagonist which has been shown to be an effective antiemetic agent for patients undergoing radiation or chemotherapy treatment. The Canadian Forces together with other NATO Countries have an interest in selecting an antiemetic agent that not only is effective in the prevention of emesis induced by chemical agents or radiation exposure, but also has minimal, if any, side effects. The purpose of this study was to examine the influence of a single 8-mg oral dose of the drug on thermoregulation during exercise in a hot (40 degrees C, 30% relative humidity) environment. Ten unacclimatized males performed a drug and placebo trial in single-blind random order. The sessions involved walking on a treadmill at 4.8 km.h-1 with a 2% elevation for a maximum of 3 h. Subjects wore combat clothing during the trials. Total exposure time was similar for the placebo (177 +/- 6 min) and drug (172 +/- 11 min) trials. Also, the rate of sweat production (0.64 +/- 0.1 and 0.66 +/- 0.1 kg.h-1 for placebo and drug, respectively) and body heat gain (303 +/- 112 and 305 +/- 110 kj for the placebo and drug, respectively) were not different between trials. Rectal temperature increased 1.48 +/- 0.40 degrees C for the placebo and 1.47 +/- 0.37 degrees C for the ondansetron trial. Finally, there was no difference in the mean skin temperature response which increased in both conditions to 37.1 +/- 0.5 degrees C. Under the conditions of this experiment, there is no evidence to suggest that the ingestion of ondansetron influences thermoregulation in a hot environment.

Adult↗
PubMed2004

Effects of a home walking exercise program on functional status and symptoms in heart failure.

BACKGROUND: Hospital-based exercise programs using a bicycle ergometer or a combination of exercise modalities have shown positive benefits in heart failure, but may not be readily accessible to many patients. Thus, we sought to evaluate the effects of a 12-week home walking exercise program on functional status and symptoms in patients with heart failure. METHODS: A randomized controlled trial comparing a 12-week progressive home walking exercise program (n = 42) to a "usual activity" control group (n = 37) was conducted in patients with heart failure (78 [99%] male; mean age 62.6 +/- 10.6 years; ejection fraction 27% +/- 8.8%; 63 [80%] New York Heart Association class II; 15[20%] New York Heart Association class III-IV) from a Veterans Affairs medical center and a university-affiliated medical center. Functional status (peak oxygen consumption via cardiopulmonary exercise testing, 6-minute walk test, the Heart Failure Functional Status Inventory), and symptoms (Dyspnea-Fatigue Index score with a postglobal rating of symptoms) were measured at baseline and 12 weeks. RESULTS: No adverse events related to exercise training occurred. Overall mean compliance to training was 74 +/- 37%. Peak oxygen consumption and the Heart Failure Functional Status Inventory were unchanged with training. Compared to the usual activity group, the training group had significantly longer walking distances measured by the 6-minute walk test (1264 +/- 255 vs 1337 +/- 272 feet, P =.001), and improved postglobal rating of symptoms (P =.03). CONCLUSION: In patients with heart failure, a progressive home walking exercise program is acceptable, increases walking distance, and decreases global rating of symptoms.

Aged↗
PubMedDate not supplied

Influence of a 6-week arm exercise program on walking ability and health status after hip arthroplasty: a 1-year follow-up pilot study.

The influence of an upper-limb interval-training program after total hip arthroplasty (THA) in elderly patients was studied during a 1 yr follow-up on health status and walking ability. After surgery, 14 patients were randomly assigned to the control group that started a 6 wk general rehabilitation program or the training group that combined it with an interval exercise program on an arm ergometer. A Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index was completed 1 mo before and 2 mo and 1 yr after surgery. A 6 min walking test was performed at 2 mo and 1 yr after surgery. The training group covered a significantly longer distance than the control group in the 6 min walk test and obtained significantly lower WOMAC scores both at 2 mo and 1 yr after surgery. However, both groups significantly improved in WOMAC and in their performance during the survey. Endurance-type upper-body aerobic training in a rehabilitation program might be important after THA.

Aged↗
PubMed2006

The effect of a worksite based walking programme on cardiovascular risk in previously sedentary civil servants [NCT00284479].

BACKGROUND: A significant proportion of Europeans do not meet the recommendations for 30 mins of physical activity 5 times per week. Whether lower frequency, moderate intensity exercise alters cardiovascular disease (CVD) risk has received little attention. This study examined the effects of 45 minutes self-paced walking, 2 d. wk(-1) on aerobic fitness, blood pressure (BP), body composition, lipids and C-Reactive Protein (CRP) in previously sedentary civil servants. METHODS: 37 subjects (24 women) aged 41.5 +/- 9.3 years were randomly assigned to either two 45 minute walks per week (walking group) or no training (control group). Aerobic fitness, body composition, blood pressure (BP), CRP and lipoprotein variables were measured at baseline and following 8 weeks. Steps counts were measured at baseline and during weeks 4 and 8 of the intervention. RESULTS: Compared to the control group, the walking group showed a significant reduction in systolic BP and maintained body fat levels (P < 0.05). There were no changes other risk factors. Subjects took significantly more steps on the days when prescribed walking was performed (9303 +/- 2665) compared to rest days (5803 +/- 2749; P < 0.001). CONCLUSION: These findings suggest that walking twice per week for 45 minutes at approximately 62% HRmax, improves activity levels, reduces systolic BP and prevents an increase in body fat in previously sedentary adults. This walking prescription, however, failed to induce significant improvements in other markers of cardiovascular disease risk following eight weeks of training.

Adult↗
PubMed2005

The efficacy of corticosteroids in periradicular infiltration for chronic radicular pain: a randomized, double-blind, controlled trial.

STUDY DESIGN: A randomized, double-blind controlled trial. OBJECTIVES: To determine the treatment effect of corticosteroids in periradicular infiltration for chronic radicular pain. We also examined prognostic factors in relation to the outcome of the procedure. SUMMARY OF BACKGROUND DATA: Various studies have examined the therapeutic value of periradicular infiltration using treatment agents consisting of local anesthetic and corticosteroids for radicular pain, secondary to lumbar disc herniation and spinal stenosis. There is currently no randomized trial to determine the efficacy of a single injection of corticosteroids for chronic radicular pain. METHODS: Eligible patients with radicular pain who had unilateral symptoms who failed conservative management were randomized for a single injection with bupivacaine and methylprednisolone or bupivacaine only. Outcome measures included the Oswestry Disability Index, visual analogue score for back pain and leg pain, claudication walking distance, and the patient's subjective level of satisfaction of the outcome. RESULTS: We recruited 43 patients in the bupivacaine and methylprednisolone group and 43 patients in the bupivacaine only group. The follow-up rate is 100%. Five patients had early termination of the trial for discectomy and further root block. There is no statistically significant difference in the outcome measures between the groups at 3 months (change of the Oswestry Disability Index [P = 0.68], change in visual analogue score [back pain, P = 0.68; leg pain, P = 0.94], change in walking distance [P = 0.7]). Duration of symptoms has a statistically significant negative association with the change in Oswestry Disability Index (P = 0.03). CONCLUSION: Clinical improvement occurred in both groups of patients. Corticosteroids did not provide additional benefit.

Adult↗
PubMed2005

Inactivity, exercise, and visceral fat. STRRIDE: a randomized, controlled study of exercise intensity and amount.

Despite the importance of randomized, dose-response studies for proper evaluation of effective clinical interventions, there have been no dose-response studies on the effects of exercise amount on abdominal obesity, a major risk factor for metabolic syndrome, diabetes, and cardiovascular disease. One hundred seventy-five sedentary, overweight men and women with mild to moderate dyslipidemia were randomly assigned to participate for 6 mo in a control group or for approximately 8 mo in one of three exercise groups: 1) low amount, moderate intensity, equivalent to walking 12 miles/wk (19.2 km) at 40-55% of peak oxygen consumption; 2) low amount, vigorous intensity, equivalent to jogging 12 miles/wk at 65-80% of peak oxygen consumption; or 3) high amount, vigorous intensity, equivalent to jogging 20 miles/wk (32.0 km). Computed tomography scans were analyzed for abdominal fat. Controls gained visceral fat (8.6 +/- 17.2%; P = 0.001). The equivalent of 11 miles of exercise per week, at either intensity, prevented significant accumulation of visceral fat. The highest amount of exercise resulted in decreased visceral (-6.9 +/- 20.8%; P = 0.038) and subcutaneous (-7.0 +/- 10.8%; P < 0.001) abdominal fat. Significant gains in visceral fat over only 6 mo emphasize the high cost of continued inactivity. A modest exercise program, consistent with recommendations from the Centers for Disease Control/American College of Sports Medicine (CDC/ACSM), prevented significant increases in visceral fat. Importantly, a modest increase over the CDC/ACSM exercise recommendations resulted in significant decreases in visceral, subcutaneous, and total abdominal fat without changes in caloric intake.

Abdominal Fat↗
PubMedDate not supplied

An intervention to promote walking in sedentary women in the community.

OBJECTIVE: To evaluate a telephone counseling intervention that was designed to help sedentary women begin and maintain a walking program. METHODS: Females (N = 197) were randomly assigned to either an intervention, attention control, or no-attention control group. Assessments were made at baseline and 6 months. RESULTS: Women in the intervention group reported more time walked each day than did control women (P < .05). The intervention worked equally for African American and European American women as well as for different income groups. CONCLUSION: Overall, a counseling intervention via telephone appears to be a good way to help women begin a walking program.

Adult↗
PubMed1983

Recombinant DNA strategies in genetic neurological diseases.

The application of recombinant DNA techniques applied to the study of genetic neurological diseases will play a major role in the practice of neurology in upcoming years. Strategies are now available to develop useful and relatively simple biochemical diagnostic tests for heterozygous individuals with diseases inherited as autosomal dominant traits. In addition, molecular genetic methods will lead to the delineation of the genomic mutations responsible for these diseases. This review will update the current status of research in several neurological genetic diseases including myotonic muscular dystrophy, Huntington's disease, Charcot-Marie-Tooth disease and Duchenne muscular dystrophy (X-linked). An introduction and overview of the methodology is provided. Specific research strategies including random screening of libraries, chromosome walking, messenger RNA selection, and messenger RNA translation are described. These strategies are designed to provide heterozygote identification, prenatal diagnosis and gestational management, the development of rational therapies, and the understanding of the molecular basis of disease expression.

Charcot-Marie-Tooth Disease↗
PubMed2002

Effects of exercise training on aerobic and functional capacity of end-stage renal disease patients.

The aim was to assess the effects of exercise training on aerobic and fuctional capacity of patients with end-stage renal disease (ESRD). Patients completed an incremental exercise test on a cycle ergometer to determine VO2 peak and VO2 at ventilatory threshold (VT; V-slope). On a separate day they performed two constant load exercise tests on a cycle ergometer at 90% of VT and at a workload of 33 W, to determine VO2 kinetics. Functional capacity was assessed using measurements of sit-to-stands (STS-5, STS-60) and a walk test. Dialysis patients were randomly allocated to an exercise (ET: n = 18, age = 57.3 years) or control (C: n = 15, age = 50.5 - 5 years) group. The ET group participated in an exercise training programme involving cycling for 3 months. Repeated measures ANOVA revealed significant time by group interactions (P < 0.05) following training for VO2 peak (ET: 17 +/- 6.1 versus 19.9 +/- 6-3, C: 19.5 +/- 4.7 versus 188 +/- 4.9 ml kg min(-1)) and VO2-VT (ET: 10.7 +/- 3.5 versus 11.8 +/- 3.3, C:12.9 +/- 3.2 versus 119 +/- 3.5 ml kg min(-10). VO2 kinetics remained unchanged in both groups at 90% -VT, but a trend (P = 0.059) towards faster kinetics at the 33 W was observed (ET: 49.6 +/- 19.5 versus 37.8 +/- 12.7, C: 42.8 +/- 13 versus 49.4 +/- 20.2 s). Significant time by group interactions (P < 0.05) were also observed for STS-5 (ET: 14.7 +/- 6.2 versus 11.0 +/- 3.3, C: 12.8 +/- 4.4 versus 12.7 +/- 4.8 s) and STS-60 measurements (ET: 21.2 + 7.2 versus 26.9 +/- 6.2, C: 23.7 +/- 6.8 versus 24.1 +/- 7.2). Three months of exercise rehabilitation significantly improves peak exercise capacity of patients with ESRD. Measurements of VO2 kinetics and functional capacity suggest that longer time might be needed to induce peripheral adaptations.

Adaptation, Physiological↗
PubMed1999

Addendum to "Quantitative measure of folding in two-dimensional polymers".

Recently, we introduced a measure of folding complexity for two-dimensional polymers, N macro, the mean radial intersection number [Phys. Rev. E 59, 4209 (1999)]. In this addendum, we expand on three aspects of the previous work. First, we provide an analytical expression for N macro that is valid for two-dimensional networks. Second, we show that the power-law scaling N macro approximately equal to n(beta), with n the number of monomers, has a different critical exponent for random and self-avoiding walks. Finally, we find that the folding features in optimized projections of experimental three-dimensional (native) protein backbones fall between the latter limit models.

Journal Article↗