Structured Exercise in Obese Diabetic Patients with Chronic Kidney Disease: A Randomized Controlled Trial.

BACKGROUND: Patients with type 2 diabetes mellitus (DM), obesity, and chronic kidney disease (CKD) are generally physically inactive and may benefit from exercise. Our objective was to determine the effects of structured exercise on physical fitness, kidney function, endothelial function, inflammation, and body composition in such patients. METHODS: In this randomized, controlled trial, 36 male patients (age 49-81) were randomly assigned to exercise + diet management (n = 18) or diet alone (n = 18). Participants were eligible if they had type 2 DM, body mass index >30 kg/m2, CKD stages 2-4, and persistent proteinuria (>200 mg/g creatinine for >3 months). The exercise intervention was a 12-week (3 days per week) program of aerobic and resistance training followed by 40 weeks of home exercise. The primary outcome measure was change from baseline in urine protein to creatinine ratio (UPCR) at 12 and 52 weeks. RESULTS: Thirty-two participants completed the study (14 exercise + diet, 18 diet-alone group). The change from baseline in UPCR was slightly greater in the diet-alone group at 12 weeks but not at 52 weeks. Changes in both symptom-limited and constant-workrate treadmill times were significantly higher in the exercise + diet group at 12 weeks but not at 52 weeks. There were no significant differences in urine albumin to creatinine ratio, estimated glomerular filtration rate, endothelial function, inflammation, or body composition between the groups. CONCLUSIONS: In obese diabetic subjects with CKD, structured exercise improved exercise capacity but not body composition or renal function. This is a work of the US Government and is not subject to copyright protection in the USA. Foreign copyrights may apply. Published by S. Karger AG, Basel.

The effects of smoking status on walking ability and health-related quality of life in patients with peripheral arterial disease.

BACKGROUND: Smoking is a leading risk factor for peripheral arterial disease (PAD), yet little is known about the interrelationships among smoking status, walking endurance, calf muscle tissue oxygenation, and quality of life in patients with PAD. OBJECTIVE: The aim of this study was to explore the differences in factors associated with walking endurance including walk distance, perceived walking ability, measures of skeletal muscle tissue oxygenation (StO2), claudication pain, peak oxygen consumption per unit time, and quality of life in smokers versus nonsmokers. METHODS: A total of 105 patients with PAD performed progressive, symptom-limited treadmill test. Ankle-brachial index was measured at baseline. Calf muscle tissue oxygenation measures were obtained during testing. The RAND Short Form-36 and Walking Impairment Questionnaire were used to measure health-related quality of life (HR-QoL). RESULTS: In the total sample (36 current smokers, 69 nonsmokers), smokers had steeper declines in StO2 from baseline to 2 minutes (42.3% vs 33%, P = .05) and shorter distance walked to onset of claudication pain (142.6 vs 247.7 m) than did nonsmokers (P < .0125), despite having no differences in ankle-brachial index, peak oxygen consumption per unit time, or any momentary measure of StO2 during walking. Smokers reported significantly lower HR-QoL on the Short Form-36 in several domains but no differences in the Walking Impairment Questionnaire measures. The smokers were younger than the nonsmokers; however, when age was entered as a covariate in the analyses, the results remained unchanged. CONCLUSIONS: These findings suggest that smokers have lower HR-QoL than do nonsmokers with PAD and that smoking confers risks for disrupted tissue oxygenation above those seen in patients who do not smoke.

Aerobic exercise in obese diabetic patients with chronic kidney disease: a randomized and controlled pilot study.

BACKGROUND: Patients with obesity, diabetes, and chronic kidney disease (CKD) are generally physically inactive, have a high mortality rate, and may benefit from an exercise program. METHODS: We performed a 24-week randomized controlled feasibility study comparing aerobic exercise plus optimal medical management to medical management alone in patients with type 2 diabetes, obesity (body mass index [BMI] > 30 kg/m2), and stage 2-4 CKD (estimated glomerular filtration rate [eGFR] 15-90 mL/min/1.73 m2 with persistent proteinuria). Subjects randomized to exercise underwent thrice weekly aerobic training for 6 followed by 18 weeks of supervised home exercise. The primary outcome variable was change in proteinuria. RESULTS: Seven subjects randomized to exercise and 4 control subjects completed the study. Exercise training resulted in an increase in exercise duration during treadmill testing, which was accompanied by slight but insignificant decreases in resting systolic blood pressure and 24-hour proteinuria. Exercise did not alter GFR, hemoglobin, glycated hemoglobin, serum lipids, or C-reactive protein (CRP). Caloric intake and body weight and composition also did not change with exercise training. CONCLUSION: Exercise training in obese diabetic patients with CKD is feasible and may have clinical benefits. A large-scale randomized controlled trial to determine the effects of exercise on renal functions, cardiovascular fitness, inflammation, and oxidative stress in diabetic patients with CKD is planned.

Can ventilation-feedback training augment exercise tolerance in patients with chronic obstructive pulmonary disease?

RATIONALE: Exercise-induced dynamic hyperinflation contributes to decreased exercise tolerance in chronic obstructive pulmonary disease (COPD). It is unknown whether respiratory retraining (ventilation-feedback [VF] training) can affect exercise-induced dynamic hyperinflation and increase exercise tolerance. OBJECTIVES: To determine whether patients with COPD would achieve longer exercise duration if randomized to a combination of exercise training plus VF training than either form of training on its own. METHODS: A total of 64 patients randomized to 1 of 3 groups: VF plus exercise (n = 22), exercise alone (n = 20), and VF alone (n = 22). MEASUREMENTS AND MAIN RESULTS: Exercise duration before and after 36 training sessions and exercise-induced dynamic hyperinflation and respiratory pattern before and after training were measured. In the 49 patients who completed training, duration of constant work-rate exercise was 40.0 (+/- 20.4) minutes (mean +/- SD) with VF plus exercise, 31.5 (+/- 17.3) minutes with exercise alone, and 16.1 (+/- 19.3) minutes with VF alone. Exercise duration was longer in VF plus exercise than in VF alone (P < 0.0001), but did not reach predetermined statistical significance when VF plus exercise was compared with exercise alone (P = 0.022) (because of multiple comparisons, P

Cardiovascular training effect associated with polestriding exercise in patients with peripheral arterial disease.

Because individuals with claudication pain secondary to peripheral arterial disease (PAD) are limited in both walking speed and duration, the benefits of walking exercise may be insufficient to yield a cardiovascular training effect. The objectives of this analysis were to determine whether polestriding exercise training, performed by persons with PAD, would improve exercise endurance, elicit a cardiovascular training benefit, and improve quality of life (QoL). Persons (n = 49) whose claudication pain limited their exercise capacity were randomized into a 24-week polestriding training program (n = 25, 65.8 +/- 7.1 years of age) or a nonexercise attention control group (n = 24, 68.0 +/- 8.6 years of age). Those assigned to the polestriding group trained 3 times weekly. Control group subjects came to the laboratory biweekly for ankle blood pressure measurements. A symptom-limited ramp treadmill test, ratings of perceived leg pain, and QoL data (using the Short Form-36) were obtained at baseline and upon completion of training. After 24 weeks of polestriding training, subjects increased their exercise endurance from 10.3 +/- 4.1 minute to 15.1 +/- 4.5 minute. This was significantly greater than control group subjects whose exercise endurance declined (from 11.2 +/- 4.7 to 10.3 +/- 4.7 minute; P < .001). Relationships between systolic blood pressure (P < .001), heart rate (P = .04), rate pressure product (P = .05), oxygen uptake (P = .016), and perceived leg pain (P = .02) and exercise time improved from the baseline symptom-limited treadmill test to the 6-month symptom-limited treadmill test in the polestriding group compared to the control group. The improvement in the physical component summary score of the Short Form-36 was also greater in the polestriding group (P = .031). Polestriding training significantly improved the clinical indicators of cardiovascular fitness and QoL, and decreased symptoms of claudication pain during exertion.

Effects of exercise training on aerobic capacity and quality of life in individuals with heart failure.

PURPOSE: The purpose of this study was to determine whether subjects with chronic heart failure, who completed a 12-week rehabilitation program, would have significantly greater quality of life, better aerobic fitness, less difficulty with symptoms of heart failure, greater self-efficacy for exercise, and higher daily activity levels when compared with subjects in a control group. METHODS: Thirty-one males, aged 64 +/- 10 years with left ventricular ejection fraction of 29 +/- 7%, were randomized to a moderate intensity supervised aerobic exercise program (n = 15) or a control group (n = 16). Twenty-seven subjects completed at least 1 follow-up assessment. RESULTS: After 12 weeks there were significant differences in the change scores for perceived physical function (using RAND Corporation's 36-item short form) (P =.025) and peak oxygen uptake (P =.019) between the exercise and control groups with the exercise group experiencing improved physical function and fitness. CONCLUSIONS: Exercise training in adults with heart failure increases exercise tolerance and perceived physical function. Improved heart failure symptoms, self-efficacy for exercise, or increased physical activity may not be associated with enhancement of exercise tolerance.

PoleStriding exercise and vitamin E for management of peripheral vascular disease.

PURPOSE: The purpose of this investigation was to evaluate the efficacy of PoleStriding exercise (a form of walking that uses muscles of the upper and lower body in a continuous movement similar to cross-country skiing) and vitamin E (alpha-tocopherol) to improve walking ability and perceived quality of life (QOL) of patients with claudication pain secondary to peripheral arterial disease (PAD). METHODS: Fifty-two subjects were randomized into four groups: PoleStriding with vitamin E (N = 13), PoleStriding with placebo (N= 14), vitamin E without exercise (N= 13), and placebo without exercise (N = 12). The dose of vitamin E was 400 IU daily. Only the PoleStriding with vitamin E and PoleStriding with placebo groups received PoleStriding instruction and training. Assignment to vitamin E or placebo was double blind. Subjects trained three times weekly for 30-45 min (rest time excluded). Individuals in vitamin E and placebo groups came to the laboratory biweekly for ankle blood-pressure measurements. RESULTS: Results of this randomized clinical trial provide strong evidence that PoleStriding significantly (P< 0.001) improved exercise tolerance on the constant work-rate and incremental treadmill tests. Ratings of perceived claudication pain were significantly less after the PoleStriding training program (P= 0.02). In contrast, vitamin E did not have a statistically significant effect on the subjects' ratings of perceived leg pain (P= 0.35) or treadmill walking duration ( P= 0.36). Perceived distance and walking speed (Walking Impairment Questionnaire) and perceived physical function (Rand Short Form-36) improved in the PoleStriding trained group only (P< 0.001, 0.022 and 0.003, respectively). CONCLUSION: PoleStriding effectively improved the exercise tolerance and perceived QOL of patients with PAD. Little additional benefit to exercise capacity was realized from vitamin E supplementation.

Increasing exercise tolerance of persons limited by claudication pain using polestriding.

OBJECTIVE: The efficacy of polestriding exercise (walking with modified ski poles with a movement pattern similar to cross-country skiing) to increase exercise tolerance of persons with intermittent claudication pain caused by peripheral arterial disease was tested in this 24-week prospective randomized clinical trial. METHODS: The study was conducted in a Department of Veterans Affairs Hospital with 52 individuals who gave written informed consent and were randomized into either a polestriding exercise (n = 27; age, 65.5 +/- 7.0 years; ankle brachial index, 0.64 +/- 0.25) or nonexercise control (n = 25; age, 68.6 +/- 8.9 years; ankle brachial index, 0.69 +/- 0.14) group (P >.05 for all comparisons). The polestriding exercise program consisted of supervised training three times per week for 4 weeks, two times per week for 8 weeks, one time per week for 4 weeks, biweekly for 4 weeks and unsupervised training for 4 weeks. Starting in week 5, subjects took their poles home with instructions to repeat the most recent supervised training walk at an appropriate and convenient location near their residence. This was referred to as unsupervised but directed exercise. Subjects were provided with a personal log book for documenting unsupervised exercise sessions. With both supervised and unsupervised exercise, subjects were expected to complete a total of four 30-minute to 45-minute polestriding exercise sessions per week. The main outcome measures were exercise duration on symptom-limited incremental treadmill test, Walking Impairment Questionnaire, rating of perceived leg pain at baseline, 4, 8, 12, 16, and 24 weeks, and constant work-rate treadmill exercise tests at baseline and at 4, 12, and 24 weeks. RESULTS: Polestriding significantly (P <.001) improved exercise tolerance on the constant work-rate and incremental treadmill tests. Ratings of perceived claudication pain were significantly less after the polestriding training program. Subject perceived distance and walking speed scores on the Walking Impairment Questionnaire improved in the polestriding trained group only (P <.001 and.022, respectively). CONCLUSION: This randomized clinical trial provides empirical evidence that 24 weeks of polestriding training significantly improves quantitative and qualitative measures of the exercise tolerance of persons limited by intermittent claudication pain.