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Recent Advances in Chest Medicine |

Pulmonary RehabilitationRecent Advances in Pulmonary Rehabilitation: A Review of the Recent Literature FREE TO VIEW

Roger S. Goldstein, MBChB, FCCP; Kylie Hill, PhD; Dina Brooks, PhD; Thomas E. Dolmage, MSc
Author and Funding Information

From the Department of Respiratory Medicine (Drs Goldstein and Brooks and Mr Dolmage) and Respiratory Diagnostic and Evaluation Services (Mr Dolmage), West Park Healthcare Centre, Toronto, ON, Canada; Department of Physical Therapy (Drs Goldstein and Brooks) and Department of Medicine (Dr Goldstein), University of Toronto, Toronto, ON, Canada; School of Physiotherapy and Curtin Health Innovation Research Institute (Dr Hill), Curtin University, Bentley, WA, Australia; and Lung Institute of Western Australia and Centre for Asthma, Allergy and Respiratory Research (Dr Hill), University of Western Australia, Crawley, WA, Australia.

Correspondence to: Roger S. Goldstein, MBChB, FCCP, Department of Respiratory Medicine, West Park Healthcare Centre, 82 Buttonwood Ave, Toronto, ON, M6M 2J5, Canada; e-mail: roger.goldstein@westpark.org


Reproduction of this article is prohibited without written permission from the American College of Chest Physicians. See online for more details.

Funding/Support: Dr Goldstein is supported by the University of Toronto-NSA Chair in Respiratory Rehabilitation Research. Dr Brooks is supported by a Canada Research Chair.


Chest. 2012;142(3):738-749. doi:10.1378/chest.12-0188
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Pulmonary rehabilitation (PR) is an evidence-based, multidisciplinary, comprehensive intervention that can be integrated into the management of individuals with chronic lung disease. It aims to reduce symptoms, optimize function, increase participation in daily life, and reduce health-care resource utilization. In this review, we summarize the new developments in PR over the past 5 years. Issues related to patient assessment include a comparison of cycle- and walking-based measures of exercise capacity, the emergence of multidimensional indices, the refinement of the minimal clinically important difference, and the importance of assessing physical activity. Issues related to exercise training focus on strategies to optimize the training load. We also comment on the acquisition of self-management skills, balance training, optimizing access, and maintaining gains following completion of PR.

Figures in this Article

In 1952, Barach et al1 reported on the importance of exercise for patients with emphysema, and in 1969, Petty et al2 described a comprehensive care program for patients with COPD that included exercise training. However, because early studies of pulmonary rehabilitation (PR) were unable to demonstrate convincing evidence of a physiologic training adaptation,3 opinions on its benefits remained equivocal. In 1991, Casaburi et al4 reported an increase in lactate threshold after high-intensity cycle training in COPD, an observation later shown to reflect improved quadriceps oxidative capacity.5 The subsequent accumulation of high-quality data to support the effectiveness of PR6,7 means that its application for those with chronic lung disease is endorsed by professional societies.8,9 PR is an evidence-based, multidisciplinary, comprehensive intervention that reduces symptoms, optimizes function, increases participation, and reduces health-care resource utilization. Its main components are supervised exercise training, self-management education, and psychosocial support. In this review, we summarize recent developments in PR, focusing on patient assessment, exercise training, and program delivery mainly for patients with COPD. The emerging evidence for PR in diseases other than COPD is briefly summarized.

Common components of patient assessment comprise measures of lung function, exercise capacity, and health-related quality of life (HRQL). Over the past 5 years, key developments pertain to the (1) choice of assessments to evaluate exercise capacity, (2) introduction of multidimensional indices, (3) refinement of the minimal clinically important difference (MCID), and (4) use of physical activity as an outcome measure.

Assessing Exercise Capacity

Compared with cycling-based assessments, it is now clear that walking can induce greater arterial oxygen desaturation,10,11 which at least in part reflects a greater ventilatory response during cycling.12 Moreover, constant power tests are more responsive than incremental tests,1315 and these protocols are recommended to demonstrate changes in exercise tolerance in response to an intervention.16 Walking assessments are more responsive than cycling assessments when evaluating the effects of bronchodilation on exercise tolerance.17 These findings will assist health-care professionals to match the assessment protocol more closely to the exercise outcomes of interest.

Multidimensional Indices

Multidimensional indices combine several constructs to formulate an aggregate score. The most well-known is the BMI, airflow obstruction, dyspnea, and exercise capacity (BODE) index, which was developed in 2004.18 The BODE index combines measures of BMI, airflow obstruction, dyspnea, and exercise capacity, thereby encompassing the pulmonary and systemic effects of COPD. The capacity of the BODE index to predict mortality varies among studies.18,19 Alternative multidimensional measures that do not include exercise capacity are the age, dyspnea, and airflow obstruction (ADO) index19; the dyspnea, airflow obstruction, smoking status, and exacerbation frequency (DOSE) index,20 and the self-reported general health, self-reported physical activity, dyspnea, and airflow obstruction (HADO) index.21 Although each of these indices has been associated with clinical events such as hospitalization or mortality,1821 many of them may have a similar capacity to predict mortality as one of the common component measures: the Medical Research Council dyspnea scale.22 Another aggregate measure is the COPD Assessment Test.23 This eight-item, valid, reliable tool can be used for evaluative or discriminatory assessments.15,23

Minimal Clinically Important Difference

The MCID is the smallest difference in score that can be detected or noticed within a homogenous patient group24 and is intended to help drive clinical decisions related to program development, such as initiating or discontinuing a particular treatment strategy. Both anchor and distribution-based methods have been used to establish an MCID, although estimates using different methodologies often are disparate. The MCID appears to depend on the intervention. For example, the MCID for the change in endurance shuttle walk test following use of a bronchodilator was 65 s, but it was closer to 186 s following a PR program.25 As they are developed from group data, the MCIDs should not be used to interpret changes in individual patients.26

Physical Activity

Robust data demonstrate that patients with COPD are inactive compared with healthy age- and sex-matched control subjects27 (Fig 1) and that this sedentary lifestyle is a predictor of clinical outcomes, including hospitalization and mortality.28,29 Although optimizing physical activity is increasingly seen as an important goal of PR, the best way to measure this outcome remains a challenge. Self-report questionnaires lack precision because of recall and social desirability bias.30 Pedometers lack sensitivity to detect the slow walking speeds characteristic of severe disease.31 Accelerometers and portable metabolic monitors, although accurate,32,33 are expensive and require technical expertise. Work done during the 6-min walk and incremental shuttle walk tests is strongly associated with average daily energy expenditure34 (Fig 2), suggesting that field-based walking tests are markers of physical activity. We still require a simple, accurate, and inexpensive measure of physical activity to evaluate the impact of PR.

Figure Jump LinkFigure 1. Percentages of time spent in each of the activities or body positions in healthy subjects and patients with COPD during the day. Others refers to cycling or undetermined activity (2% in healthy elderly subjects and 3% in patients with COPD). Reprinted with permission of the American Thoracic Society. Copyright © 2012 American Thoracic Society. Pitta F, Troosters T, Spruit MA, Probst VS, Decramer M, Gosselink R. Characteristics of physical activities in daily life in chronic obstructive pulmonary disease. Am J Respir Crit Care Med 2005;171:972-977. Official Journal of the American Thoracic Society.Grahic Jump Location
Figure Jump LinkFigure 2. A, B, Correlation (solid line) and 95% prediction intervals (dashed lines) for the relationship between average daily energy expenditure and (A) body weight-walking distance product for the 6MWT (r = 0.73, P < .001) and (B) body weight-walking distance product for the ISWT (r = 0.75, P < .001). 6MWT = 6-min walk test; ISWT = incremental shuttle walk test. (Reprinted with permission from Hill et al.34)Grahic Jump Location

Aerobic exercise training increases exercise tolerance, reduces dyspnea and fatigue, improves HRQL,6 and reduces health-care resource utilization.35 Training loads > 60% of maximum exercise capacity are associated with physiologic adaptation.4,8 However, not all patients can tolerate high-intensity training,36 and some experience little improvement in exercise capacity.37 These so-called nonresponders are characterized by a profound ventilatory limitation to exercise37 such that the training intensity is constrained by intolerable symptoms.36 Even for those who can tolerate training intensities at a high percentage of their peak aerobic capacity, the training load in absolute terms is modest.38 Recent training initiatives that have focused on reducing the extent to which the ventilatory limitation during exercise curtails the training stimulus include (1) interval training, (2) changing the gas inspired during exercise, (3) ventilatory strategies such as noninvasive ventilation, (4) transcutaneous electrical muscle stimulation (TCEMS), and (5) partitioning the exercising muscles. Because evidence for these strategies has been derived from studies of patients with COPD, their effectiveness in patients with other respiratory conditions is unknown. Moreover, initiatives such as noninvasive positive pressure ventilation (NIPPV), which increases the training stimulus borne by the peripheral muscles by reducing the ventilatory load, may be of less value if coexisting heart failure is the main mechanism of exercise limitation.

Strategies to Optimize Training
Interval Training:

Using fixed intervals of high-intensity exercise interspersed with low-intensity exercise or rest has been shown to elicit physiologic training effects consistent with skeletal muscle conditioning in healthy adults39 and those with advanced COPD.40 The high-intensity exercise maximizes training stimulants, and the low-intensity or rest intervals allow for relief of dyspnea or leg fatigue. A recent meta-analysis of eight trials (388 patients) that compared interval to continuous exercise noted no differences between groups in the magnitude of effect between the training approaches,41 a finding supported by a recent Cochrane review.42 However, the interval training protocols varied considerably between studies, and, therefore, the most efficacious approach remains a topic of interest. In clinical practice, an interval-based training program can be implemented in the absence of sophisticated equipment. However, until the patient learns to alternate work and rest periods and manipulate work rates independently, interval training will require a higher staff-to-patient ratio than continuous training.

Manipulating the Inspired Gas:
Supplemental Oxygen—

In COPD, increasing the Fio2 during exercise reduces ventilation, hyperinflation, and dyspnea43 in a dose-dependent manner (maximum gains at an Fio2 of 50%).44 Short-term benefits have been shown, even among those who do not desaturate to ≤ 88% on exertion.44,45 However, supplemental oxygen during exercise training in those who are not hypoxemic at rest remains controversial. A meta-analysis of five randomized controlled trials (RCTs)46 in which patients trained while breathing either supplemental oxygen or ambient air noted an increase in cycle exercise endurance (weighted mean difference, 2.7 min; 95% CI, 0.1-5.3 min) and reduced dyspnea on test completion (Borg scale weighted mean difference, −1.2; 95% CI, −2.4 to −0.1) but no differences in maximum power, peak rate of oxygen uptake, performance during field-based walking tests, or HRQL. Studies have reported no benefit on physical activity or HRQL when supplemental oxygen was prescribed for domiciliary use in these patients.4749

Heliox and Helium-Hyperoxia—

Replacing nitrogen with helium decreases airway resistance in the medium and large airways. In the laboratory setting, 79% helium and 21% oxygen (heliox [HO]) increases inspiratory capacity, reduces dynamic hyperinflation, reduces dyspnea, and increases cycle endurance [mean ± SD, 4.2 ± 2.0 to 9.0 ± 4.5 min; P < .001].50 At submaximal exercise intensities, HO also increases muscle blood flow,51 which enhances oxygen delivery to the quadriceps and improves exercise endurance.52 Changing the inspired gas from HO to 60% helium and 40% oxygen (helium-hyperoxia [HH]) confers additional benefits in cycle53 and walking54 endurance in COPD, especially in those with more severe airflow obstruction.

A training study of HH demonstrated greater gains in cycle exercise endurance in the HH group compared with the ambient air control group (9.5 ± 9.1 min vs 4.3 ± 6.3 min, P < .05).55 Despite higher exercise intensity and training duration in the HH group (P < .05) (Fig 3), on completion of training, there were no differences between groups in the peak rate of oxygen uptake.55 In another study, 2 months of exercise training with HH did not confer additional gains in peak exercise capacity or exercise endurance compared with supplemental oxygen or ambient air.56

Figure Jump LinkFigure 3. Mean exercise training variables across the 6-week rehabilitation program in the air (�) or helium-hyperoxia (□) groups. A, Training intensity. B, Duration of exercise. The dashed lines indicate the duration of exercise prescribed, whereas the symbols depict the duration of exercise completed. Values are presented as mean ± SD. *P < .05 in the helium-hyperoxia group vs air group. (Reprinted with permission from Eves et al.55)Grahic Jump Location

In clinical practice, barriers to the widespread use of supplemental oxygen, HO, and HH during PR include cost and awkwardness of administration. Moreover, it is unclear whether using these gases will confer a sustainable benefit. Supplemental oxygen at home is infrequently used,57,58 and neither HO nor HH are likely to be offered outside of the hospital setting.

Ventilatory Strategies:
Noninvasive Positive Pressure Ventilation—

NIPPV reduces the inspiratory work of breathing, enhances oxygenation of the quadriceps, decreases dyspnea, and increases exercise capacity.5961 A literature review62 reported that greater gains in exercise capacity in a group that trained with NIPPV compared with no ventilatory assistance was an inconsistent finding. The application of nocturnal NIPPV during PR in patients with mild hypercapnic respiratory failure was associated with small improvements in daytime arterial blood gases and gains in some components of HRQL.63 Ongoing implementation of NIPPV together with community PR served to sustain these gains 2 years following randomization and to confer greater gains in 6-min walk distance (6MWD).64 In clinical practice, the cost and technical support requirements for NIPPV will preclude its use in the community as an adjunct to exercise training.

Ventilation-Feedback—

A novel ventilatory strategy used a computerized ventilation-feedback (VF) system to set a slow respiratory rate and prolong expiratory time. Collins et al65 undertook an RCT in which patients with COPD received either exercise training plus VF, exercise alone, or VF alone. The use of VF during exercise reduced hyperinflation more than exercise training alone, and adding VF to exercise training tended to confer greater gains in exercise endurance than exercise training alone (P = .051). Further study is needed to confirm these findings. Uptake in clinical practice may be limited by the need for sophisticated equipment and the time needed to teach the technique to patients.

Transcutaneous Electrical Muscle Stimulation:

Muscles may be conditioned without voluntary contraction using TCEMS. The stimulation protocol should target specific aspects of muscle function. The electrical training protocol is defined by the pulse frequency (5-100 Hz), the duration of stimulation and rest periods (ie, on and off times), and the number of repetitions. A protocol designed to increase strength must induce forceful contractions using the highest tolerated current intensity without inducing fatigue and can do so at high frequencies (50-100 Hz), with long on times and much longer off times over a few total repetitions (< 15).66,67 An endurance protocol aims to elicit fatigue using a low pulse frequency (eg, 8 Hz); brief (2-4 s), but similar on and off times; and repetitions for a longer duration (30-60 min). In healthy subjects, such protocols improve muscle endurance, capillary density, and oxidative enzyme activity.68

In 2002, the application of TCEMS for patients with COPD was encouraged by the publication of positive trials showing that electrical stimulation for 6 weeks conferred greater gains in muscle function and exercise capacity compared with control subjects.69,70 Bourjeily-Habr et al69 stimulated the quadriceps, hamstring, and calf muscles and reported gains in strength and the distance achieved during the incremental shuttle walk test. Neder et al70 stimulated the quadriceps and demonstrated an increase in muscle strength, peak rate of oxygen uptake, and cycle exercise endurance. A study of home TCEMS (50 Hz) reported that improvement in quadriceps force, endurance, and cross-sectional area was associated with a more favorable muscle anabolic-to-catabolic ratio.71 Changes in muscle cross-sectional area and force-generating capacity were related to the stimulation intensity achieved. Because patients who could not tolerate large increases in stimulation intensity had only minimal increase in walking endurance, TCEMS may be of limited benefit to them.71

Although the stated goal of TCEMS is to improve strength, most studies also aim to improve endurance, so patients were stimulated with high frequencies (50 Hz) and a low ratio of on to off time. In contrast to these hybrid strength and endurance protocols, Nuhr et al72 stimulated the quadriceps and hamstring muscles in patients with chronic heart failure daily for 10 weeks using low frequency (15 Hz) and a high ratio of on to off time (impulse trains for 2 s, interrupted by 4 s for 2 h bid). This protocol targeted endurance by closely simulating brief rhythmic ambulatory muscle contraction, resulting in improved oxidative enzymes, anaerobic threshold, and 6MWD.

Work investigated the cardiorespiratory responses to TCEMS. During a single application, both low- and high-frequency TCEMS elicited similar rates of oxygen uptake, minute ventilation, heart rate, and symptoms of dyspnea that were just above those expected at rest but well below that expected of conventional whole-body (ie, walking) training.73 This finding suggests that both forms of stimulation would be acceptable therapeutic options in the rehabilitation environment.

In 2011, Abdellaoui et al74 reported that TCEMS (35 Hz) increased quadriceps force, type 1 muscle fibers, and 6MWD in patients hospitalized with an acute exacerbation of COPD (AECOPD). This study extends previous work by Zanotti et al,75 who noted that for patients with COPD who were invasively ventilated following an AECOPD, TCEMS plus active limb exercise improved muscle strength and decreased the time to transfer from bed to chair; these gains were greater than any seen in a group who performed active limb exercise without TCEMS. Given the very low cardiopulmonary stress associated with TCEMS, establishing the optimal stimulation protocol for its use will continue to be of interest in the area of PR.

Partitioning the Exercising Muscle Mass:

In 2006, Dolmage and Goldstein76 reported that during incremental cycle exercise, patients with COPD achieved the same peak rate of oxygen uptake while cycling with one leg as they did with two legs. Compared with cycling with two legs, cycling with one leg during prolonged endurance time by 17 min, meaning that by limiting the total exercising muscle volume, a high-intensity training stimulus could be provided with less ventilatory load. In an RCT of one- vs two-leg cycle training for 30 min three times per week for 7 weeks, the between-group difference in the peak rate of oxygen uptake was 0.19 L/min (95% CI, 0.09-0.29 L/min).77

In 2009, Bjørgen et al78 compared one- vs two-leg cycling using an interval training approach and noted a significant between-group difference in change in the peak rate of oxygen uptake (single leg, 0.20 L/min; two legs, 0.09 L/min) (Fig 4). No additional benefit was conferred by increasing the Fio2 during one-leg training.83 Although the implementation of one-leg cycle training in clinical practice requires only a simple adaptation of a cycle ergometer, the impact of this training approach on outcomes such as HRQL remains to be determined.

Figure Jump LinkFigure 4. Forest plot demonstrating overall effect for difference in peak rate of oxygen uptake achieved with one- vs two-legged cycling. This figure has been published previously as follows: (i) Pulmonary Rehabilitation. Evans RA, Goldstein RS. In: Physical Medicine and Rehabilitation: Principles and Applications, Book Series of Comprehensive Biomedical Physics; Copyright Elsevier; Figure 7 (in press)79; (ii) Evans RA, Goldstein RS. Role of Pulmonary Rehabilitation in COPD. Focus on COPD. 2010;1(4):8-1280; (iii) Evans RA, Goldstein RS. Pulmonary rehabilitation. In: SK Jindal, eds. Handbook of Pulmonary and Critical Care Medicine. New Delhi, India: Jaypee Brothers Medical Publishers Ltd; 2010; Figure 1181; and (iv) Evans RA, Goldstein RS. Pulmonary rehabilitation: an overview including new and innovative strategies-reprinted by permission of Edizioni Minerva Medica from: Minerva Pneumologica. 2011;50(1):47-61.82Grahic Jump Location
Increasing Peripheral Muscle Strength

Quadriceps cross-sectional area is a predictor of mortality independent of lung function.84 Reductions in muscle volume lead to impairments in force-generating capacity, which in turn, decreases exercise capacity,85 reduces balance,86 and increases fall risk.87 Because aerobic exercise training confers little increase in muscle strength,88 resistance training, nutritional support, testosterone, and dietary creatine supplementation have been explored as strategies to increase muscle mass. Although resistance training increases force-generating capacity,89 and these gains may be enhanced with the use of testosterone,90 it is unclear whether this confers additional improvements in performance above aerobic exercise training alone.89 The impact of nutritional interventions91 and creatine supplementation92 remains inconclusive, creating a need for additional investigation in this area.

Arm Training

Systematic reviews93,94 of RCTs examining the effect of arm training in COPD noted improvements in arm exercise performance, and RCTs of arm training completed after these systematic reviews have confirmed improvements in arm muscle strength, arm exercise performance, arm function, and ease of performing activities of daily living.95,96 Costi et al95 reported that 15 sessions over 3 weeks of arm training during PR that comprised five unsupported arm exercises performed at 50% of the patient’s maximum force improved arm function and activities of daily living at the end of the study and at 6-month follow-up. In 2011, Janaudis-Ferreira et al96 reported that 6 weeks of arm training performed three times a week during PR at loads equal to the 10- to 12-repetition maximum using free weights and a multistation gym conferred between-group differences in arm function, arm exercise capacity, and muscle strength. These data support the inclusion of an arm training program in PR.

Fall Risk

Individuals with COPD have reductions in all subcomponents of postural control, including biomechanical constraints, stability limits/verticality, anticipatory postural adjustments for postural transitions, reactive postural response strategies, weighting of sensory information for orientation, and postural stability during gait.86 In response to balance perturbations, they have an increased center of pressure displacement and a delayed reaction time for balance recovery.86,97 Almost one-half of the individuals in a PR program reported at least one fall in the preceding year,98 and almost one-third of those under the care of a pulmonologist reported a fall over a 6-month period.99 Clinical balance tests, number of medications, and comorbid conditions discriminate between self-reported fallers and nonfallers,98,99 with balance confidence and the use of supplemental oxygen being independent predictors of falls.98 PR without specific balance training does not affect balance in a meaningful way.100 The role of a balance training program to reduce falls in those at greatest risk remains to be reported.

Rollator Prescription

The use of a rollator (ie, wheeled walker) has been shown to confer gains in 6MWD and reduce dyspnea on exertion.101 Such changes appear to be the consequence of the forward lean position and fixation of the arms, serving to optimize ventilatory capacity as well as improved mechanical efficiency.102,103 Although those who need to rest during a 6-min walk test are most likely to benefit from the use of a rollator,101 whether these devices enhance exercise training among those with the greatest functional limitations is unknown.

Self-Management

Self-management teaches the skills for patients to comply with disease-specific treatment; guides health behavior changes; and assists patients to optimize their coping skills, mastery, and self-efficacy related to their chronic condition.104 It often includes disease-specific education, action plans, and goal setting. A Cochrane review of self-management revealed reductions in hospitalizations and a small improvement in HRQL.104 Because studies noting reduced hospitalizations or faster recovery from AECOPD have combined aspects of self-management education with access to a case manager,105,106 it is important to clarify which support intervention was the major influence on the observed improvements.

Psychologic Support

Anxiety and depression are common in COPD107 and have been associated with poor exercise capacity, worse HRQL, greater dyspnea, and increased health-care resource utilization.108,109 Data from a meta-analysis of six RCTs demonstrate that comprehensive PR reduces anxiety and depression,110 the main responsible component being exercise training.111 Although studies on cognitive behavioral therapy in COPD suggest a reduction in psychologic distress,112,113 it is unclear whether these gains are over and above those seen following a comprehensive PR program or which patients are most likely to benefit.

Acute Exacerbations

Acute exacerbations have deleterious effects on physical activity,114 muscle function,115 exercise capacity, and HRQL.116 Studies have demonstrated that PR is safe and effective during or immediately following an AECOPD. Man et al117 reported that PR within 10 days of discharge from the hospital improved the distance walked during an incremental shuttle walk test (between-group difference, 60 m; 95% CI, 27-93 m), and Seymour et al118 extended these observations to include a reduction in readmission to the hospital for repeat exacerbations (usual care vs PR, 33% vs 7%; OR, 0.15; 95% CI, 0.03-0.72). Work demonstrated that resistance exercise performed during hospitalization for AECOPD optimized muscle force without increasing systemic inflammation.119 It is possible that for patients hospitalized with an AECOPD, resistance exercise added to standard early mobilization followed by ongoing participation in PR after discharge will emerge as a pattern of best practice.

Improving Access

PR is mostly offered at hospital outpatient settings, and long journey time and parking costs limit attendance or program completion.120 A multicenter Canadian study demonstrated similar outcomes between PR provided in an outpatient department and PR at home.121 Those who trained at home received a visit from an exercise specialist to establish the training program, were assigned a cycle ergometer for use in their home, and were encouraged through weekly telephone calls.121 Therefore, home-based PR, if appropriately resourced, offers an alternate approach to accessing this service for patients with COPD.

Another barrier to providing PR, particularly in remote settings, is the perception that an effective exercise program is contingent on the availability of expensive equipment, such as treadmills and cycle ergometers. However, a study demonstrated that high-intensity ground walking performed in isolation from other forms of exercise training was effective at increasing functional exercise capacity,14 suggesting that the exercise component of PR can be effectively delivered in the absence of sophisticated exercise equipment. Access to PR in remote settings might be facilitated by the use of telemedicine. In 2011, a study that provided access to an established PR program through videoconferencing plus some local clinic resources reported gains in HRQL and exercise capacity of similar magnitude to those achieved following outpatient PR.122 Other technology applications with a potential to enhance PR include the use of cell phones and motion sensors to encourage physical activity during daily life123,124 and interactive Internet-based interfaces to provide education and guidance regarding self-management of dyspnea and exercise.125

Maintaining Benefits

Regular physical activity after formal PR slows the decline in HRQL126 and may decrease hospital admissions and mortality.29 Completion of annual repeat PR programs confers short-term gains without long-term benefits after 2 years.127 Monthly supervised exercise training plus regular telephone contact after PR does not maintain gains128,129 nor does monthly visits to a physiotherapist offered in conjunction with abbreviated PR following an AECOPD.130 In contrast, weekly classes at a hospital or community setting appears to preserve improvements following PR.131,132 The issue of long-term adherence to PR will require a more integrated approach between health facilities and community facilities.

Respiratory Conditions Other Than COPD

Over the past few years, RCT data have emerged to support the effectiveness of exercise training in persons with interstitial lung disease,133 life-long asthma,134 bronchiectasis,135 and pulmonary hypertension.136 Over the next few years, data from current RCTs will be available to support the effectiveness of PR in chronic lung diseases other than COPD.137139

PR has a positive impact on exercise capacity, HRQL, dyspnea, and fatigue6 and reduces health-care resource utilization.35 Recent interest in the systemic nature of COPD has resulted in the use of multidimensional indices. There are exciting novel approaches to optimize training in patients with marked ventilatory limitation to exercise, and evidence is increasing to support PR in respiratory conditions other than COPD. Issues that continue to challenge us include (1) optimizing access to PR, (2) translating gains in exercise capacity into increased physical activity, (3) strategies to maintain the gains made during PR, (4) minimizing the deleterious effects of AECOPD, and (5) establishing whether PR confers a survival benefit.

Financial/nonfinancial disclosures: The authors have reported to CHEST that no potential conflicts of interest exist with any companies/organizations whose products or services may be discussed in this article.

Role of sponsors: The sponsors had no role in the design of the study, the collection and analysis of the data, or in the preparation of the manuscript.

6MWD

6-min walk distance

AECOPD

acute exacerbation of COPD

BODE

BMI, airflow obstruction, dyspnea, and exercise capacity

HH

helium-hyperoxia

HO

heliox

HRQL

health-related quality of life

MCID

minimal clinically important difference

NIPPV

noninvasive positive pressure ventilation

PR

pulmonary rehabilitation

RCT

randomized controlled trial

TCEMS

transcutaneous electrical muscle stimulation

VF

ventilation-feedback

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van Wetering CR, Hoogendoorn M, Mol SJ, Rutten-van Mölken MP, Schols AM. Short- and long-term efficacy of a community-based COPD management programme in less advanced COPD: a randomised controlled trial. Thorax. 2010;65(1):7-13. [PubMed] [CrossRef]
 
Cockram J, Cecins N, Jenkins S. Maintaining exercise capacity and quality of life following pulmonary rehabilitation. Respirology. 2006;11(1):98-104. [PubMed] [CrossRef]
 
Spencer LM, Alison JA, McKeough ZJ. Maintaining benefits following pulmonary rehabilitation: a randomised controlled trial. Eur Respir J. 2010;35(3):571-577. [PubMed] [CrossRef]
 
Holland A, Hill C. Physical training for interstitial lung disease. Cochrane Database Syst Rev. 2008;4):CD006322.
 
Turner S, Eastwood P, Cook A, Jenkins S. Improvements in symptoms and quality of life following exercise training in older adults with moderate/severe persistent asthma. Respiration. 2011;81(4):302-310. [PubMed] [CrossRef]
 
Newall C, Stockley RA, Hill SL. Exercise training and inspiratory muscle training in patients with bronchiectasis. Thorax. 2005;60(11):943-948. [PubMed] [CrossRef]
 
Mereles D, Ehlken N, Kreuscher S, et al. Exercise and respiratory training improve exercise capacity and quality of life in patients with severe chronic pulmonary hypertension. Circulation. 2006;114(14):1482-1489. [PubMed] [CrossRef]
 
Lee AL, Cecins N, Hill CJ, et al. The effects of pulmonary rehabilitation in patients with non-cystic fibrosis bronchiectasis: protocol for a randomised controlled trial. BMC Pulm Med. 2010;10:5. [PubMed] [CrossRef]
 
Jones LW, Eves ND, Kraus WE, et al. The lung cancer exercise training study: a randomized trial of aerobic training, resistance training, or both in postsurgical lung cancer patients: rationale and design. BMC Cancer. 2010;10:155. [PubMed] [CrossRef]
 
Ganderton L, Jenkins S, Gain K, et al. Short term effects of exercise training on exercise capacity and quality of life in patients with pulmonary arterial hypertension: protocol for a randomised controlled trial. BMC Pulm Med. 2011;11:25. [PubMed] [CrossRef]
 

Figures

Figure Jump LinkFigure 1. Percentages of time spent in each of the activities or body positions in healthy subjects and patients with COPD during the day. Others refers to cycling or undetermined activity (2% in healthy elderly subjects and 3% in patients with COPD). Reprinted with permission of the American Thoracic Society. Copyright © 2012 American Thoracic Society. Pitta F, Troosters T, Spruit MA, Probst VS, Decramer M, Gosselink R. Characteristics of physical activities in daily life in chronic obstructive pulmonary disease. Am J Respir Crit Care Med 2005;171:972-977. Official Journal of the American Thoracic Society.Grahic Jump Location
Figure Jump LinkFigure 2. A, B, Correlation (solid line) and 95% prediction intervals (dashed lines) for the relationship between average daily energy expenditure and (A) body weight-walking distance product for the 6MWT (r = 0.73, P < .001) and (B) body weight-walking distance product for the ISWT (r = 0.75, P < .001). 6MWT = 6-min walk test; ISWT = incremental shuttle walk test. (Reprinted with permission from Hill et al.34)Grahic Jump Location
Figure Jump LinkFigure 3. Mean exercise training variables across the 6-week rehabilitation program in the air (�) or helium-hyperoxia (□) groups. A, Training intensity. B, Duration of exercise. The dashed lines indicate the duration of exercise prescribed, whereas the symbols depict the duration of exercise completed. Values are presented as mean ± SD. *P < .05 in the helium-hyperoxia group vs air group. (Reprinted with permission from Eves et al.55)Grahic Jump Location
Figure Jump LinkFigure 4. Forest plot demonstrating overall effect for difference in peak rate of oxygen uptake achieved with one- vs two-legged cycling. This figure has been published previously as follows: (i) Pulmonary Rehabilitation. Evans RA, Goldstein RS. In: Physical Medicine and Rehabilitation: Principles and Applications, Book Series of Comprehensive Biomedical Physics; Copyright Elsevier; Figure 7 (in press)79; (ii) Evans RA, Goldstein RS. Role of Pulmonary Rehabilitation in COPD. Focus on COPD. 2010;1(4):8-1280; (iii) Evans RA, Goldstein RS. Pulmonary rehabilitation. In: SK Jindal, eds. Handbook of Pulmonary and Critical Care Medicine. New Delhi, India: Jaypee Brothers Medical Publishers Ltd; 2010; Figure 1181; and (iv) Evans RA, Goldstein RS. Pulmonary rehabilitation: an overview including new and innovative strategies-reprinted by permission of Edizioni Minerva Medica from: Minerva Pneumologica. 2011;50(1):47-61.82Grahic Jump Location

Tables

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Janaudis-Ferreira T, Hill K, Goldstein R, Wadell K, Brooks D. Arm exercise training in patients with chronic obstructive pulmonary disease: a systematic review. J Cardiopulm Rehabil Prev. 2009;29(5):277-283. [PubMed]
 
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Costi S, Crisafulli E, Antoni FD, Beneventi C, Fabbri LM, Clini EM. Effects of unsupported upper extremity exercise training in patients with COPD: a randomized clinical trial. Chest. 2009;136(2):387-395. [PubMed] [CrossRef]
 
Janaudis-Ferreira T, Hill K, Goldstein RS, et al. Resistance arm training in patients with COPD: A Randomized Controlled Trial. Chest. 2011;139(1):151-158. [PubMed] [CrossRef]
 
Smith MD, Chang AT, Seale HE, Walsh JR, Hodges PW. Balance is impaired in people with chronic obstructive pulmonary disease. Gait Posture. 2010;31(4):456-460. [PubMed] [CrossRef]
 
Beauchamp MK, Hill K, Goldstein RS, Janaudis-Ferreira T, Brooks D. Impairments in balance discriminate fallers from non-fallers in COPD. Respir Med. 2009;103(12):1885-1891. [PubMed] [CrossRef]
 
Roig M, Eng JJ, MacIntyre DL, et al. Falls in people with chronic obstructive pulmonary disease: an observational cohort study. Respir Med. 2011;105(3):461-469. [PubMed] [CrossRef]
 
Beauchamp MK, O’Hoski S, Goldstein RS, Brooks D. Effect of pulmonary rehabilitation on balance in persons with chronic obstructive pulmonary disease. Arch Phys Med Rehabil. 2010;91(9):1460-1465. [PubMed] [CrossRef]
 
Solway S, Brooks D, Lau L, Goldstein R. The short-term effect of a rollator on functional exercise capacity among individuals with severe COPD. Chest. 2002;122(1):56-65. [PubMed] [CrossRef]
 
Probst VS, Troosters T, Coosemans I, et al. Mechanisms of improvement in exercise capacity using a rollator in patients with COPD. Chest. 2004;126(4):1102-1107. [PubMed] [CrossRef]
 
Hill K, Dolmage TE, Woon LJ, Brooks D, Goldstein RS. Rollator use does not consistently change the metabolic cost of walking in people with chronic obstructive pulmonary disease [published online ahead of print March 29, 2012]. Arch Phys Med Rehabil. doi:10.1016/j.apmr.2012.01.009.
 
Effing T, Monninkhof EM, van der Valk PD, et al. Self-management education for patients with chronic obstructive pulmonary disease. Cochrane Database Syst Rev. 2007;4):CD002990.
 
Bourbeau J, Julien M, Maltais F, et al;. Chronic Obstructive Pulmonary Disease axis of the Respiratory Network Fonds de la Recherche en Santé du Québec Chronic Obstructive Pulmonary Disease axis of the Respiratory Network Fonds de la Recherche en Santé du Québec. Reduction of hospital utilization in patients with chronic obstructive pulmonary disease: a disease-specific self-management intervention. Arch Intern Med. 2003;163(5):585-591. [PubMed] [CrossRef]
 
Trappenburg JC, Monninkhof EM, Bourbeau J, et al. Effect of an action plan with ongoing support by a case manager on exacerbation-related outcome in patients with COPD: a multicentre randomised controlled trial. Thorax. 2011;66(11):977-984. [PubMed] [CrossRef]
 
Hill K, Geist R, Goldstein RS, Lacasse Y. Anxiety and depression in end-stage COPD. Eur Respir J. 2008;31(3):667-677. [PubMed] [CrossRef]
 
Xu W, Collet JP, Shapiro S, et al. Independent effect of depression and anxiety on chronic obstructive pulmonary disease exacerbations and hospitalizations. Am J Respir Crit Care Med. 2008;178(9):913-920. [PubMed] [CrossRef]
 
von Leupoldt A, Taube K, Lehmann K, Fritzsche A, Magnussen H. The impact of anxiety and depression on outcomes of pulmonary rehabilitation in patients with COPD. Chest. 2011;140(3):730-736. [PubMed] [CrossRef]
 
Coventry PA, Hind D. Comprehensive pulmonary rehabilitation for anxiety and depression in adults with chronic obstructive pulmonary disease: Systematic review and meta-analysis. J Psychosom Res. 2007;63(5):551-565. [PubMed] [CrossRef]
 
Emery CF, Schein RL, Hauck ER, MacIntyre NR. Psychological and cognitive outcomes of a randomized trial of exercise among patients with chronic obstructive pulmonary disease. Health Psychol. 1998;17(3):232-240. [PubMed] [CrossRef]
 
Kunik ME, Veazey C, Cully JA, et al. COPD education and cognitive behavioral therapy group treatment for clinically significant symptoms of depression and anxiety in COPD patients: a randomized controlled trial. Psychol Med. 2008;38(3):385-396. [PubMed] [CrossRef]
 
Hynninen MJ, Bjerke N, Pallesen S, Bakke PS, Nordhus IH. A randomized controlled trial of cognitive behavioral therapy for anxiety and depression in COPD. Respir Med. 2010;104(7):986-994. [PubMed] [CrossRef]
 
Pitta F, Troosters T, Probst VS, Spruit MA, Decramer M, Gosselink R. Physical activity and hospitalization for exacerbation of COPD. Chest. 2006;129(3):536-544. [PubMed] [CrossRef]
 
Spruit MA, Gosselink R, Troosters T, et al. Muscle force during an acute exacerbation in hospitalised patients with COPD and its relationship with CXCL8 and IGF-I. Thorax. 2003;58(9):752-756. [PubMed] [CrossRef]
 
Carr SJ, Goldstein RS, Brooks D. Acute exacerbations of COPD in subjects completing pulmonary rehabilitation. Chest. 2007;132(1):127-134. [PubMed] [CrossRef]
 
Man WD, Polkey MI, Donaldson N, Gray BJ, Moxham J. Community pulmonary rehabilitation after hospitalisation for acute exacerbations of chronic obstructive pulmonary disease: randomised controlled study. BMJ. 2004;329(7476):1209. [PubMed] [CrossRef]
 
Seymour JM, Moore L, Jolley CJ, et al. Outpatient pulmonary rehabilitation following acute exacerbations of COPD. Thorax. 2010;65(5):423-428. [PubMed] [CrossRef]
 
Troosters T, Probst VS, Crul T, et al. Resistance training prevents deterioration in quadriceps muscle function during acute exacerbations of chronic obstructive pulmonary disease. Am J Respir Crit Care Med. 2010;181(10):1072-1077. [PubMed] [CrossRef]
 
Sabit R, Griffiths TL, Watkins AJ, et al. Predictors of poor attendance at an outpatient pulmonary rehabilitation programme. Respir Med. 2008;102(6):819-824. [PubMed] [CrossRef]
 
Maltais F, Bourbeau J, Shapiro S, et al;. Chronic Obstructive Pulmonary Disease Axis of Respiratory Health Network, Fonds de recherche en santé du Québec Chronic Obstructive Pulmonary Disease Axis of Respiratory Health Network, Fonds de recherche en santé du Québec. Effects of home-based pulmonary rehabilitation in patients with chronic obstructive pulmonary disease: a randomized trial. Ann Intern Med. 2008;149(12):869-878. [PubMed]
 
Stickland M, Jourdain T, Wong EY, Rodgers WM, Jendzjowsky NG, Macdonald GF. Using Telehealth technology to deliver pulmonary rehabilitation in chronic obstructive pulmonary disease patients. Can Respir J. 2011;18(4):216-220. [PubMed]
 
de Blok BM, de Greef MH, ten Hacken NH, Sprenger SR, Postema K, Wempe JB. The effects of a lifestyle physical activity counseling program with feedback of a pedometer during pulmonary rehabilitation in patients with COPD: a pilot study. Patient Educ Couns. 2006;61(1):48-55. [PubMed] [CrossRef]
 
Nguyen HQ, Gill DP, Wolpin S, Steele BG, Benditt JO. Pilot study of a cell phone-based exercise persistence intervention post-rehabilitation for COPD. Int J Chron Obstruct Pulmon Dis. 2009;4:301-313. [PubMed] [CrossRef]
 
Nguyen HQ, Donesky-Cuenco D, Wolpin S, et al. Randomized controlled trial of an internet-based versus face-to-face dyspnea self-management program for patients with chronic obstructive pulmonary disease: pilot study. J Med Internet Res. 2008;10(2):e9. [PubMed] [CrossRef]
 
Heppner PS, Morgan C, Kaplan RM, Ries AL. Regular walking and long-term maintenance of outcomes after pulmonary rehabilitation. J Cardiopulm Rehabil. 2006;26(1):44-53. [PubMed] [CrossRef]
 
Foglio K, Bianchi L, Ambrosino N. Is it really useful to repeat outpatient pulmonary rehabilitation programs in patients with chronic airway obstruction? A 2-year controlled study. Chest. 2001;119(6):1696-1704. [PubMed] [CrossRef]
 
Brooks D, Krip B, Mangovski-Alzamora S, Goldstein RS. The effect of postrehabilitation programmes among individuals with chronic obstructive pulmonary disease. Eur Respir J. 2002;20(1):20-29. [PubMed] [CrossRef]
 
Ries AL, Kaplan RM, Myers R, Prewitt LM. Maintenance after pulmonary rehabilitation in chronic lung disease: a randomized trial. Am J Respir Crit Care Med. 2003;167(6):880-888. [PubMed] [CrossRef]
 
van Wetering CR, Hoogendoorn M, Mol SJ, Rutten-van Mölken MP, Schols AM. Short- and long-term efficacy of a community-based COPD management programme in less advanced COPD: a randomised controlled trial. Thorax. 2010;65(1):7-13. [PubMed] [CrossRef]
 
Cockram J, Cecins N, Jenkins S. Maintaining exercise capacity and quality of life following pulmonary rehabilitation. Respirology. 2006;11(1):98-104. [PubMed] [CrossRef]
 
Spencer LM, Alison JA, McKeough ZJ. Maintaining benefits following pulmonary rehabilitation: a randomised controlled trial. Eur Respir J. 2010;35(3):571-577. [PubMed] [CrossRef]
 
Holland A, Hill C. Physical training for interstitial lung disease. Cochrane Database Syst Rev. 2008;4):CD006322.
 
Turner S, Eastwood P, Cook A, Jenkins S. Improvements in symptoms and quality of life following exercise training in older adults with moderate/severe persistent asthma. Respiration. 2011;81(4):302-310. [PubMed] [CrossRef]
 
Newall C, Stockley RA, Hill SL. Exercise training and inspiratory muscle training in patients with bronchiectasis. Thorax. 2005;60(11):943-948. [PubMed] [CrossRef]
 
Mereles D, Ehlken N, Kreuscher S, et al. Exercise and respiratory training improve exercise capacity and quality of life in patients with severe chronic pulmonary hypertension. Circulation. 2006;114(14):1482-1489. [PubMed] [CrossRef]
 
Lee AL, Cecins N, Hill CJ, et al. The effects of pulmonary rehabilitation in patients with non-cystic fibrosis bronchiectasis: protocol for a randomised controlled trial. BMC Pulm Med. 2010;10:5. [PubMed] [CrossRef]
 
Jones LW, Eves ND, Kraus WE, et al. The lung cancer exercise training study: a randomized trial of aerobic training, resistance training, or both in postsurgical lung cancer patients: rationale and design. BMC Cancer. 2010;10:155. [PubMed] [CrossRef]
 
Ganderton L, Jenkins S, Gain K, et al. Short term effects of exercise training on exercise capacity and quality of life in patients with pulmonary arterial hypertension: protocol for a randomised controlled trial. BMC Pulm Med. 2011;11:25. [PubMed] [CrossRef]
 
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