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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

Hypogonadism, found in about one-third of patients with chronic obstructive pulmonary disease (COPD), has potential for decreasing muscle mass and muscle performance. Compared with eugonadal patients, we hypothesized that hypogonadal patients with COPD have decreased respiratory and skeletal muscle performance. Nineteen hypogonadal and 20 eugonadal men with COPD (FEV[1] 1.14 +/- 0.08 and 1.17 +/- 0.11 L [standard error], respectively) were studied. Diaphragmatic contractility, assessed as transdiaphragmatic twitch pressure generated by phrenic nerve stimulation, was similar in hypogonadal and eugonadal patients: 20.6 +/- 2.2 and 19.8 +/- 2.5 cm H2O, respectively. During progressive inspiratory threshold loading, hypogonadal and eugonadal patients had similar respiratory muscle endurance times (302 +/- 29 and 313 +/- 48 seconds, respectively) and airway pressure sustained during the last minute of loading (38.2 +/- 3.0 and 40.5 +/- 4.7 cm H2O, respectively) (similar to predicted values in healthy subjects). Hypogonadal and eugonadal patients had equivalent limb muscle strength and endurance. During cycle exercise to exhaustion, exercise performance, gas exchange, and respiratory muscle recruitment (estimated by esophageal and gastric pressure swings during tidal breathing) were similar in both groups. In conclusion, hypogonadism does not decrease respiratory or limb muscle performance and exercise capacity in men with moderate-to-severe COPD who, for the most part, are not underweight. [ABSTRACT FROM AUTHOR]

The purpose of this study was to assess the effects of applying transcutaneous electrical stimulation to paralyzed abdominal muscles during pulmonary function testing (PFT) of individuals with spinal cord injury (SCI). Ten male subjects with anatomical level of SCI between C5-T7 were studied. Subjects performed PFTs with and without electrical stimulation delivered to the abdominal muscles. Subjects with the lowest percentage of predicted expiratory volumes and flows demonstrated the greatest improvement when electrical stimulation was delivered during forced expiration. The overall increases seen in percent of predicted for the study sample were 23 percent for forced vital capacity (FVC), 16 percent for forced expiratory flow in 1 s (FEV1), and 22 percent for peak expiratory flow rate (PEF). Contractions of paralyzed expiratory muscles in response to electrical stimulation during the performance of PFT maneuvers can significantly improve FVC, FEV1, and PEF in some individuals with SCI. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine if individuals with Parkinson's disease (PD) who completed an 8-week, supervised PoleStriding exercise program would undergo significant improvements in cognitive skills, activities of daily living, motor function, and quality of life. The Unified Parkinson's Disease Rating Scale (UPDRS) and the Parkinson's Disease Questionnaire (PDQ-39) were used to measure functional independence. Six male volunteers (72.7+/-3.7 years of age) performed PoleStriding exercise three times per week for 37+/-3 minutes. Differences in the participants' pre- and post-training scores on the UPDRS and PDQ-39 were analyzed using the Wilcoxin Signed Ranks Test. A statistically significant improvement occurred in the UPDRS (P<0.026) and PDQ-39 (P<0.028) scores following the moderate-intensity exercise intervention. The results of this nonrandomized clinical trial indicate that an 8-week individualized PoleStriding exercise program increases perceived functional independence and quality of life in individuals with PD. [ABSTRACT FROM AUTHOR]

The extreme difficulty with which persons with severe disabilities have been taught to maneuver a power wheelchair has been described in case studies, and anecdotal evidence suggests the existence of a patient population for whom mobility is severely limited if not impossible given currently available power wheelchair control interfaces. Since our review of the literature provided little evidence either in support or refutation of the adequacy of existing power wheelchair control interfaces, we surveyed 200 practicing clinicians, asking them to provide information about their patients and to give their impressions of the potential usefulness of a new power wheelchair navigation technology. Significant survey results were:* Clinicians indicated that 9 to 10 percent of patients who receive power wheelchair training find it extremely difficult or impossible to use the wheelchair for activities of daily living.* When asked specifically about steering and maneuvering tasks, the percentage of patients reported to find these difficult or impossible jumped to 40%.* Eighty-five percent of responding clinicians reported seeing some number of patients each year who cannot use a power wheelchair because they lack the requisite motor skills, strength, or visual acuity. Of these clinicians, 32% (27% of all respondents) reported seeing at least as many patients who cannot use a power wheelchair as who can.* Nearly half of patients unable to control a power wheelchair by conventional methods would benefit from an automated navigation system, according to the clinicians who treat them. [ABSTRACT FROM AUTHOR]

Seven subjects with chronic paralysis due to spinal cord injury completed a series of experiments to 1) determine and compare the metabolic cost of propelling the Handbike and Rowcycle, and 2) evaluate the potential of these upper body-powered devices for improving the cardiorespiratory fitness of persons with lower limb disabilities. Mean intrasubject differences between the Handbike and Rowcycle rides for heart rate, minute ventilation, oxygen uptake, and net locomotive energy cost were small and did not reach statistical significance for any of the ride conditions. Lower net locomotive energy cost (greater economy) during a 5.5 mi-hr(-1) ride condition predicted vehicle preference in all cases (P=0.008). The range of values for percent peak oxygen uptake suggests that all but one of the subjects were able to utilize either vehicle at an intensity sufficient for improving and maintaining cardiorespiratory fitness without undue fatigue. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the efficacy of a unique program of ventilation-feedback training combined with leg-cycle exercise to improve exertional endurance and decrease perceived dyspnea in patients with chronic obstructive pulmonary disease (COPD). Thirty-nine patients (67.5 +/- 8.1 yr of age) with moderate to severe COPD (42.6% of predicted forced expiratory volume in 1 s) were randomized to one of three 6-week experimental interventions: ventilation-feedback with exercise (V(+EX)), exercise only (EX(ONLY)), or ventilation-feedback only (VF(ONLY)). At baseline and at 6 weeks, patients completed a constant work-rate leg-cycle ergometer test at 85 percent of maximal power output. There were increases within the groups in exercise duration: 11.5 min (103%), 8.0 min (66%), and 0.4 min (4%) for the VF(+EX), EX(ONLY) and VF(ONLY) groups, respectively. The VF(ONLY) group experienced no significant within-group changes in selected gas exchange parameters. However, there were significant (p < 0.05) posttraining changes in minute ventilation, tidal volume, breathing frequency (f), and expiratory time (Te) in the VF(+EX) group, and in f and Te in the EX(ONLY) group. After completing the training, VF(+EX) and EX(ONLY) patients reported less breathlessness and perceived exertion (p < 0.05). The VF(ONLY) patients' ratings changed in the hypothesized direction but were not significant. Based on these preliminary data, VF(+EX) and EX(ONLY) were equally effective in improving leg-cycle exercise tolerance in patients with moderate to severe COPD. [ABSTRACT FROM AUTHOR]