Jennifer A. Alison

Parkinson's disease: An investigation of exercise capacity, respiratory function, and gait

OBJECTIVE To evaluate the exercise capacity of subjects with mild to moderate Parkinsons disease and determine whether abnormalities in respiratory function and gait affect exercise capacity. DESIGN Descriptive. Subjects were categorized according to exercise history, disease severity, and presence/absence of upper airway obstruction. SUBJECTS AND SETTING Sixteen volunteers with mild to moderate idiopathic Parkinsons disease attended a university research laboratory. MAIN OUTCOME MEASURES Subjects performed a maximum exercise test on a cycle ergometer, together with respiratory function tests and a walking test. Peak values for oxygen consumption and work rate were recorded for the maximum exercise test. Measures of respiratory function included spirometry, flow-volume loops, lung volumes, and mouth pressures. Velocity, stride length, and cadence were measured for preferred and fast speeds of walking. The values obtained on each of these tests were compared with published predicted age- and gender-matched normal values. RESULTS Peak oxygen consumptions and peak work loads achieved by subjects with Parkinsons disease were not significantly different from normal values, despite evidence of respiratory and gait abnormalities typical of Parkinsons disease. Exercise category was significantly correlated with percent predicted VO2peak (r = .64, p < .01), with sedentary subjects producing lower scores than exercising subjects. There was no significant correlation between disease severity and percent predicted VO2peak. CONCLUSION Despite their neurological deficit, individuals with mild to moderate Parkinsons disease have the potential to maintain normal exercise capacity with regular aerobic exercise.

Relationship between field walking tests and incremental cycle ergometry in COPD

Background and objective:  Cycle ergometer training is an important component of pulmonary rehabilitation for patients with COPD. However, incremental cycle tests from which individualized cycle training intensity can be prescribed may not be readily available to clinicians. The aims of the study were to (i) investigate the physiological and psychophysical responses to the 6‐min walk test (6MWT), incremental shuttle walk test (ISWT) and cycle ergometer test (CET); and (ii) determine whether the distance walked in either the 6MWT or the ISWT could be used to estimate peak work rate on a cycle ergometer.

Maintaining benefits following pulmonary rehabilitation: a randomised controlled trial

The aim of this study was to determine if weekly, supervised, outpatient-based exercise plus unsupervised home exercise following an 8-week pulmonary rehabilitation programme would maintain functional exercise capacity and quality of life at 12 months better than standard care of unsupervised home exercise training. Chronic obstructive pulmonary disease (COPD) subjects completed an 8-week pulmonary rehabilitation programme, were randomised to an intervention group (IG) of weekly, supervised, exercise plus home exercise or to a control group (CG) of unsupervised home exercise and followed for 12 months. Outcome measurements at baseline (after pulmonary rehabilitation), and 3, 6 and 12 months included the 6-min walk test and St Georges Respiratory Questionnaire (SGRQ). 59 subjects with moderate COPD (Global Initiative for Chronic Obstructive Lung Disease stage II) were recruited and 48 subjects completed the study. 12-month mean difference showed no significant change from baseline in 6-min walk distance (IG -11 m, 95% CI -21–10 m; CG -6 m, 95% CI -34–11 m) or total SGRQ score (IG 3, 95% CI -0.8–7; CG -3, 95% CI -7–3). 12 months following pulmonary rehabilitation both weekly, supervised, outpatient-based exercise plus unsupervised home exercise and standard care of unsupervised home exercise successfully maintained 6-min walk distance and quality of life in subjects with moderate COPD.

Physiological responses to the early mobilisation of the intubated, ventilated abdominal surgery patient

The aim of this study was to investigate the effects of mobilisation on respiratory and haemodynamic variables in the intubated, ventilated abdominal surgical patient. Mobilisation was defined as the progression of activity from supine, to sitting over the edge of the bed, standing, walking on the spot for one minute, sitting out of bed initially, and sitting out of bed for 20 minutes. Seventeen patients with age (mean +/- SD) 71.4 +/- 7.1 years satisfied inclusion criteria. Respiratory and haemodynamic parameters were measured in each of the above positions and compared with supine. In the 15 subjects who completed the protocol, standing resulted in significant increases in minute ventilation (VE) from 15.1 +/- 3.1 l/min in supine to 21.3 +/- 3.6 l/min in standing (p < 0.001). The increase in VE in standing was achieved by significant increases in tidal volume (VT) from 712.7 +/- 172.8 ml to 883.4 +/- 196.3 ml (p = 0.008) and in respiratory rate (fR) from 21.4 +/- 5.0 breaths/min to 24.9 +/- 4.5 breaths/min (p = 0.03). No further increases were observed in these parameters beyond standing when activity was progressed to walking on the spot for one minute. When supine values were compared with walking on the spot for one minute, inspiratory flow rates (VT/TI) increased significantly from 683 +/- 131.8 ml/sec to 985.1 +/- 162.3 ml/sec (p = 0.001) with significant increases in rib cage displacement (p = 0.001) and no significant increase in abdominal displacement (p = 0.23). Arterial blood gases displayed no improvements following mobilisation. Changes in VT, fR, and VE were largely due to positional changes when moving from supine to standing.

A randomized controlled trial of the effects of intensive sit-to-stand training after recent traumatic brain injury on sit-to-stand performance

Objective: To examine the effectiveness of intensive practice of sit-to-stand on motor performance, exercise capacity and exercise efficiency in traumatic brain-injured patients during early inpatient rehabilitation. Design: Single-blind randomized controlled pilot study. Setting: Brain injury rehabilitation unit. Subjects: Twenty-four subjects who had recently sustained a severe traumatic brain injury (TBI) were randomized into an experimental (n = 13) and a control (n = 11) group. Interventions: In addition to their usual rehabilitation programme, subjects in the experimental group participated in four weeks of intensive training of sit-to-stand and step-up exercises with the aim of improving performance of sit-to-stand. The control group did no additional sit-to-stand or step-up training. Main outcome measures: Total number of sit-to-stands in 3 min as a measure of motor performance; peak oxygen consumption during a maximal 3-min sit-to-stand test (VO2peak) as a measure of exercise capacity; oxygen consumption during a 3-min equivalent workload sit-to-stand test (VO2equiv) as a measure of exercise efficiency. Pre- and post-training measurements were made. Results: The exercise programme resulted in a 62% improvement in motor performance (number of repetitions of sit-to-stand in 3 min) for the experimental group compared with the control groups 18% improvement (p < 0.05). There was no significant difference between groups for changes in exercise capacity or efficiency. In the experimental group, the increase in VO2peak from pre-test to post-test correlated with the increase in sit-to-stand repetitions (p < 0.05). Conclusions: Intensive task-specific training is recommended as an important component of rehabilitation early following severe traumatic brain injury.

Physiological effects of vibration in subjects with cystic fibrosis

The physiological mechanisms by which vibration and other physiotherapy interventions may clear secretions in subjects with cystic fibrosis are unknown. The main aim of this study was to compare the expiratory flow rates and frequencies of airflow oscillation of vibration to those of Acapella®, Flutter®, positive expiratory pressure and percussion. Respiratory flow rates were measured during interventions, the order of which was randomised. The oscillation of the airflow of the interventions was determined by frequency spectral analysis. In 18 young adult subjects with cystic fibrosis, the mean peak expiratory flow rate of vibration was greater than Flutter®, percussion, Acapella® and positive expiratory pressure. The mean±sd of the oscillation of the airflow of vibration (8.4±0.4 Hz) was lower than Acapella® (13.5±1.7 Hz) and Flutter® (11.3±1.5 Hz) but similar to percussion (7.3±0.3 Hz). Theoretically, the higher peak expiratory flow rate of vibration compared to the other physiotherapy interventions may promote secretion clearance. In addition, the frequency of oscillation of vibration was within the range demonstrated to increase mucus transport. This study has provided some evidence for the physiological rationale for the use of vibration to aid secretion clearance.

Water-based exercise in COPD with physical comorbidities: a randomised controlled trial

Land-based exercise is often difficult for people with chronic obstructive pulmonary disease (COPD) who have coexisting obesity or musculoskeletal or neurological conditions. This randomised controlled trial aimed to determine the effectiveness of water-based exercise training in improving exercise capacity and quality of life compared to land-based exercise training and control (no exercise) in people with COPD and physical comorbidities. Participants referred to pulmonary rehabilitation were randomly allocated to a water-based exercise, land-based exercise or the control group. The two exercise groups trained for 8 weeks, completing three sessions per week. 45 out of 53 participants (mean±sd age 72±9 years; forced expiratory volume in 1 s 59±15% predicted) completed the study. Compared to controls, water-based exercise training significantly increased 6-min walking distance, incremental and endurance shuttle walk distances, and improved Chronic Respiratory Disease Questionnaire (CRDQ) dyspnoea and fatigue. Compared to land-based exercise training, water-based exercise training significantly increased incremental shuttle walk distance (mean difference 39 m, 95% CI 5–72 m), endurance shuttle walk distance (mean difference 228 m, 95% CI 19–438 m) and improved CRDQ fatigue. Water-based exercise training was significantly more effective than land-based exercise training and control in increasing peak and endurance exercise capacity and improving aspects of quality of life in people with COPD and physical comorbidities.

Short-form Sun-style T'ai Chi as an exercise training modality in people with COPD

The aims of the study were to determine the effect of short-form Sun-style t’ai chi (SSTC) (part A) and investigate exercise intensity of SSTC (part B) in people with chronic obstructive pulmonary disease (COPD). Part A: after confirmation of eligibility, participants were randomly allocated to either the t’ai chi group or control group (usual medical care). Participants in the t’ai chi group trained twice weekly for 12 weeks. Part B: participants who had completed training in the t’ai chi group performed a peak exercise test (incremental shuttle walk test) and SSTC while oxygen consumption (VO2) was measured. Exercise intensity of SSTC was determined by the per cent of VO2 reserve. Of 42 participants (mean±sd forced expiratory volume in 1 s 59±16% predicted), 38 completed part A and 15 completed part B. Compared to control, SSTC significantly increased endurance shuttle walk time (mean difference 384 s, 95% CI 186–510); reduced medial-lateral body sway in semi-tandem stand (mean difference -12.4 mm, 95% CI -21– -3); and increased total score on the chronic respiratory disease questionnaire (mean difference 11 points, 95% CI 4–18). The exercise intensity of SSTC was 53±18% of VO2 reserve. SSTC was an effective training modality in people with COPD achieving a moderate exercise intensity which meets the training recommendations.

Ground walk training improves functional exercise capacity more than cycle training in people with chronic obstructive pulmonary disease (COPD): a randomised trial

QUESTIONS Does an eight-week program of walk training improve endurance walking capacity in people with COPD compared to cycle training? Does walk training improve peak walking capacity, cycle capacity, and quality of life compared to cycle training? Is the endurance shuttle walk test (ESWT) responsive to change in walking capacity elicited by exercise training? DESIGN Randomised trial with concealed allocation, assessor blinding, and intention-to-treat analysis. PARTICIPANTS 36 people with stable COPD recruited with four dropouts. INTERVENTION Participants were randomised into either a walk or cycle training group. Both groups trained indoors for 30 to 45 minutes per session, three times weekly over eight weeks at Concord Hospital. Training intensities were based on baseline peak exercise tests and progressed as able. OUTCOME MEASURES The primary outcome was endurance walking capacity measured by the ESWT. Secondary outcomes included peak walking capacity, peak and endurance cycle capacity, and health-related quality of life. Measures were taken at baseline (Week 0) and following training (Week 8). RESULTS The walk training group increased their endurance walking time by 279 seconds (95% CI 70 to 483) more than the cycle training group. No significant differences between the groups were found for any other outcome. CONCLUSION Ground walk training increased endurance walking capacity more than cycle training and was similar to cycle training in improving peak walking capacity, peak and endurance cycle capacity and quality of life. This study provides evidence for ground walking as a mode of exercise training in pulmonary rehabilitation programs.

Assessing physical function and activity for survivors of a critical illness: A review of instruments

BACKGROUND Functional outcomes and health-related quality of life are important measures for survivors of a critical illness. Studies have demonstrated debilitating physical effects for a significant proportion of surviving patients, particularly those with intensive care unit-acquired weakness. Contemporary practice changes include a focus on the continuum of critical illness, with less sedation and more physical activity including mobility while in ICU, and post-ICU and post-hospitalisation activities to support optimal recovery. How to best assess the physical function of patients at different phases of their recovery and rehabilitation is therefore important. PURPOSE This narrative review paper examined observational and functional assessment instruments used for assessing patients across the in-ICU, post-ICU and post-hospital continuum of critical illness. METHODS Relevant papers were identified from a search of bibliographic databases and a review of the reference list of selected articles. The clinimetric properties of physical function and HRQOL measures and their relevance and utility in ICU were reported in narrative format. FINDINGS The review highlighted many different instruments used to measure function in survivors of ICU including muscle strength testing, functional tests and walk tests, and patient centred outcomes such as health related quality of life. In general, the sensitivity and validity of these instruments for use with survivors of a critical illness has not yet been established. CONCLUSION Based on findings from the review, screening of patients using reliable and valid instruments for ICU patients is recommended to inform both practice and future studies of interventions aimed at improving recovery and rehabilitation.