Shuttle Walk Test

Abstract

The Shuttle Walk Test (predominantly utilized as the Incremental Shuttle Walk Test [ISWT], alongside its fixed-rate derivative, the Endurance Shuttle Walk Test [ESWT]) is a standardized, externally paced, symptom-limited maximal field exercise test designed to assess functional exercise capacity and cardiorespiratory fitness. Originally developed by Sally J. Singh and colleagues in 1992 to overcome the pacing limitations and ceiling effects associated with self-paced functional tests such as the 6-Minute Walk Test (6MWT), the ISWT adapts the principles of the 20-meter shuttle run test (Léger & Lambert, 1982) to clinical populations characterized by cardiorespiratory compromise. Performed on a 10-meter flat course between two turning markers, the test requires participants to walk at a progressive speed governed by standardized acoustic signals emitted from an audio track. The protocol comprises 12 graded levels spanning a total of 1020 meters over a maximum duration of 12 minutes, beginning at an initial velocity of 0.50 m/s (1.8 km/h) and incrementally increasing by 0.17 m/s (approximately 0.6 km/h) each minute. Psychometrically, the ISWT exhibits robust measurement properties across chronic obstructive pulmonary disease (COPD), chronic heart failure (CHF), pulmonary hypertension, interstitial lung disease, and peripheral arterial disease. Criterion validity against gold-standard cardiopulmonary exercise testing (CPET) is high, with strong correlations observed between total distance walked and peak oxygen uptake (VO₂peak; r = 0.70 to 0.88). Test-retest reliability is exceptionally high (intraclass correlation coefficient [ICC] exceeding 0.88 to 0.99), though a documented learning effect necessitates at least one familiarization trial. The minimal clinically important difference (MCID) has been consistently established at approximately 35 to 47.5 meters (or roughly four shuttles) in cardiorespiratory populations.

Keywords

Shuttle Walk Test, Incremental Shuttle Walk Test, ISWT, functional exercise capacity, cardiorespiratory fitness, chronic obstructive pulmonary disease, exercise tolerance, cardiopulmonary exercise testing, peak oxygen uptake, psychometrics, rehabilitation outcomes

Authors

The Incremental Shuttle Walk Test was conceptualized, validated, and published by Sally J. Singh, Ann E. Morgan, S. Scott, D. Walters, and P. J. Hardman in 1992.

• Sally J. Singh, PhD, FERS: Professor of Pulmonary and Cardiac Rehabilitation, Department of Respiratory Sciences, University of Leicester; Head of Pulmonary and Cardiac Rehabilitation, University Hospitals of Leicester NHS Trust, Glenfield Hospital, Leicester, United Kingdom.
• Ann E. Morgan: Department of Respiratory Medicine, Glenfield General Hospital, Leicester, United Kingdom.
• Collaborators: Department of Respiratory Medicine, Glenfield Hospital, Leicester, United Kingdom.
• Adaptations & Guidelines: The Koninklijk Nederlands Genootschap voor Fysiotherapie (Royal Dutch Society for Physical Therapy; KNGF) formalized the Dutch clinical adaptation and operational standard within the KNGF-richtlijn Hartrevalidatie (Cardiac Rehabilitation Guidelines) in 2011.

Purpose

The primary clinical and research objective of the Shuttle Walk Test is to deliver an objective, symptom-limited, graded assessment of maximal physical functional capacity under standardized conditions without requiring sophisticated, costly, and invasive laboratory equipment such as metabolic gas-exchange analyzers or motorized treadmills. In chronic cardiorespiratory and metabolic diseases—such as chronic obstructive pulmonary disease (COPD), heart failure, cystic fibrosis, and post-cardiac surgery states—systemic pathophysiological impairments lead to profound exercise intolerance, exertional dyspnea, peripheral muscle fatigue, and progressive physical deconditioning.

Prior to the development of the ISWT, clinical evaluation of functional mobility relied heavily on self-paced corridor walking tests, most notably the 6-Minute Walk Test (6MWT) and 12-Minute Walk Test. Although the 6MWT reflects activities of daily living and functional endurance, its self-paced nature introduces substantial variance linked to psychological factors, including self-regulation, fluctuating motivation, pacing strategies, and institutional encouragement. Furthermore, in higher-functioning patients or those with mild-to-moderate impairment, self-paced tests suffer from ceiling effects, failing to stress the cardiopulmonary system to its physiological maximum. Conversely, laboratory-based cardiopulmonary exercise testing (CPET) utilizing cycle ergometers or treadmills provides precise physiological metrics (such as VO₂peak, anaerobic threshold, and ventilatory efficiency), but its widespread clinical utility is constrained by high equipment costs, technical complexity, requirement for specialist physician oversight, and physical movement constraints that do not replicate native ambulation.

The ISWT addresses these operational limitations by implementing an externally paced, progressive, incremental protocol. By utilizing prerecorded auditory bleeps that dictate an escalating walking velocity, the test minimizes individual pacing decisions and ensures that the workload increases continuously until the participant reaches maximal symptom-limited capacity. Consequently, the test fulfills multiple clinical and empirical roles:

• Baseline Functional Stratification: Quantifying exercise limitation to guide individualized prescription in pulmonary and cardiac rehabilitation programs.
• Evaluative Sensitivity: Serving as a responsive outcome measure capable of detecting subtle, clinically meaningful shifts in physiological capacity resulting from pharmacological interventions (e.g., bronchodilators, inotropes), surgical procedures (e.g., lung volume reduction, valve replacement), or structured exercise training.
• Prognostic Stratification: Establishing survival probability, hospitalization risk, and perioperative risk profiles based on total distance achieved.
• Physiological Extrapolation: Providing a validated proxy estimation of maximal oxygen uptake (VO₂peak) through established linear regression equations.

Psychological Construct

Although the Shuttle Walk Test is predominantly operationalized as a physiological assessment of exercise tolerance, performance on the test is fundamentally determined by an integrated psychophysiological construct. The final test score (distance walked in meters) does not reflect cardiorespiratory mechanics in isolation; rather, it represents the behavioral manifestation of a complex interplay between sensory afferent signaling, central perceptual processing, self-efficacy, task-focused motivation, and psychological tolerance of distressing somatic sensations.

Perceived Exertion and Symptom Tolerance

At the center of the construct is the perceptual processing of respiratory effort (dyspnea) and peripheral muscular fatigue (exertional leg tiredness). During incremental exercise, the central motor command generates an efferent copy (corollary discharge) sent to sensory areas of the cerebral cortex simultaneously with motor outflow to the skeletal and ventilatory muscles. As physiological strain escalates, the neuroventilatory disparity—the mismatch between central motor drive and mechanical respiratory response—generates an overwhelming perception of air hunger and breathing effort. Participants continuously evaluate these interoceptive cues against psychological coping thresholds. The decision to terminate the test is an active behavioral choice driven by the intersection of physiological exhaustion and perceptual tolerance.

Behavioral Compliance with External Auditory Pacing

Unlike self-paced paradigms where individuals modulate speed to remain within an affective comfort zone, the ISWT forces the individual into an external locus of pacing control. The standardized acoustic beeps compel the participant to suppress instinctive avoidance behaviors triggered by exertional discomfort. Consequently, the test measures an individual’s psychological persistence, regulatory willpower, and ability to coordinate motor output under time pressure. The construct taps into cognitive load and attention allocation: patients must synchronize turning mechanics and step velocity with auditory cues while processing escalating internal distress.

Exertion-Related Anxiety and Kinesiophobia

In clinical populations suffering from chronic cardiorespiratory disease, dyspnea and tachycardia frequently acquire conditioned threat values. Patients often develop high levels of kinesiophobia (fear of movement or physical activity) rooted in catastrophic misinterpretations of bodily sensations, anticipating that extreme breathlessness signals impending asphyxiation, cardiovascular collapse, or death. In the ISWT, this heightened somatic anxiety can induce premature voluntary cessation long before true cardiovascular or ventilatory limits are attained. Conversely, high exercise self-efficacy—the subjective conviction that one can maintain physical exertion despite somatic distress—allows participants to persist through escalating protocol tiers.

Theoretical Framework

The Shuttle Walk Test is framed at the nexus of cardiorespiratory exercise physiology, psychophysical sensory scaling, and social cognitive theory.

Cardiorespiratory Physiology and the Fick Principle

From an exercise physiology standpoint, the ISWT is grounded in the linear relationship between progressive external mechanical work rate and oxidative metabolic demand. According to the Fick principle, total oxygen consumption (VO₂) is the product of cardiac output (heart rate × stroke volume) and the arteriovenous oxygen difference (C(a-v)O₂):

VO₂ = HR × SV × (C_aO₂ − C_vO₂)

In healthy individuals and clinical cohorts alike, as walking velocity increases incrementally by 0.17 m/s each minute, metabolic demand escalates in a stepwise fashion. In healthy adults, incremental work proceeds until systemic oxygen delivery plateaus, establishing a true VO₂max governed by cardiovascular and peripheral muscular limits. In contrast, in patients with ventilatory limitations (such as airflow obstruction in COPD or restrictive chest wall pathology), dynamic lung hyperinflation, intrinsic positive end-expiratory pressure, and critical inspiratory mechanical constraints prevent further ventilation increases, causing the ventilatory reserve to exhaust prior to cardiovascular exhaustion. The theoretical design of the ISWT assumes that its stepped velocity profile increases metabolic demand symmetrically to a formal laboratory ramp treadmill or cycle CPET, eliciting identical peak cardiopulmonary biomarkers (heart rate, lactate accumulation, carbon dioxide production, and oxygen desaturation).

Borg’s Psychophysical Range Model

The subjective appraisal of work in the ISWT is theoretically operationalized through Gunnar Borg’s Psychophysical Category-Ratio Scaling model (the Borg CR10 scale). Borg’s Range Principle posits that sensory systems scale perceptual intensity relative to individual biological perceptual ranges: an individual anchors a subjective rating of ‘0’ to total rest, and ’10’ (or maximal) to the absolute sensory ceiling of exertion or breathlessness experienced. The psychological framework assumes that interoceptive somatic strain is quantifiable, reproducible, and anchored to proportional physiological strain (percentage of maximum heart rate, fraction of peak ventilation). Integrating the Borg scale before and immediately following the ISWT allows clinicians to determine whether termination was precipitated by subjective ventilatory failure, peripheral muscular exhaustion, or non-physiological factors.

Bandura’s Self-Efficacy Theory

Albert Bandura’s Social Cognitive Theory provides the psychological basis for performance variability during maximal physical tasks. Exercise self-efficacy—the individual’s perceived capability to execute the physical behaviors necessary to achieve designated physical outcomes—governs emotional arousal, task persistence, and effort expenditure when facing physical obstacles. In patients undergoing the ISWT, somatic symptoms (palpitations, deep panting, diaphoresis) act as internal cognitive feedback. If self-efficacy is low, these somatic indicators are interpreted as signals of failure or danger, triggering early behavioral disengagement. When self-efficacy is fortified through pulmonary rehabilitation or prior successful familiarization walks, the patient cognitively reframes these same symptoms as expected physiological adaptations, thereby improving total shuttle distance independent of acute improvements in pulmonary architecture.

Validity

The validity of the Shuttle Walk Test as an index of exercise capacity and functional impairment has been verified across clinical and epidemiological literature.

Criterion and Concurrent Validity

Criterion validity has been established by directly correlating ISWT metrics against gold-standard cardiopulmonary exercise testing (CPET) parameters. In the foundational validation investigation by Singh et al. (1992), incremental shuttle walking distance (ISWD) exhibited a strong positive correlation with directly measured peak oxygen uptake (VO₂peak; r = 0.88, p < 0.001) in patients with chronic airflow limitation. Subsequent cross-validation studies confirmed these findings in chronic heart failure (CHF) populations, reporting correlations ranging from r = 0.70 to r = 0.84 between ISWD and cycle ergometry VO₂peak (Lewis et al., 2001; Morales et al., 1999). Furthermore, metabolic gas-exchange investigations during the ISWT demonstrate that peak physiological responses—specifically peak heart rate, peak respiratory exchange ratio (RER > 1.05), peak blood lactate concentration, and peak ventilatory equivalent for oxygen—do not differ significantly from those recorded at maximal CPET, validating the ISWT as a true maximal test rather than an intermediate submaximal test.

Construct and Convergent Validity

Construct validity is substantiated through predictable convergent relationships with other indices of disease severity and functional performance. The ISWT correlates robustly with the self-paced 6-Minute Walk Test (typically r = 0.80 to 0.90), yet consistently discriminates levels of functional impairment with greater precision at the upper end of performance due to the absence of the ceiling effect inherent to the 6MWT. In patients with COPD, ISWD declines systematically across worsening Global Initiative for Chronic Obstructive Lung Disease (GOLD) spirometric stages (Stage I to IV; forced expiratory volume in 1 second [FEV₁] vs. ISWD typically r = 0.40 to 0.60). In heart failure, ISWD correlates inversely with New York Heart Association (NYHA) functional class (p < 0.001) and plasma levels of B-type natriuretic peptide (BNP).

Convergent validity is also verified against patient-reported outcome measures (PROMs) reflecting health-related quality of life. Moderate-to-strong negative correlations are consistently found between ISWD and scores on the St. George’s Respiratory Questionnaire (SGRQ) (r = −0.45 to −0.65) and the Chronic Respiratory Disease Questionnaire (CRQ), confirming that physical performance on the 10-meter course aligns with everyday functional independence and perceived health status.

Predictive and Prognostic Validity

The ISWT holds high predictive validity regarding clinical endpoints such as all-cause mortality, cardiovascular mortality, acute exacerbations, and hospital admissions. In patients with COPD, an ISWD of less than 170 meters is an independent predictor of premature all-cause mortality, conferring a hazard ratio significantly higher than that predicted by FEV₁ alone. In patients with heart failure referred for cardiac transplantation, performance on the ISWT adds substantial prognostic power to standard prognostic models: failing to achieve 450 meters identifies individuals with elevated risks of cardiac death and emergency hospitalization over a 24-month horizon.

Minimal Clinically Important Difference (MCID)

Through distribution-based and anchor-based psychometric techniques (anchoring against the SGRQ, CRQ, and Global Rating of Change scales), the MCID of the ISWT in patients undergoing pulmonary rehabilitation has been pinpointed at 35 to 47.5 meters (roughly equivalent to 4 to 5 shuttles) (Singh et al., 2008; Holland et al., 2014). An intervention demonstrating a mean gain equal to or greater than this threshold represents a clinically tangible functional improvement to the patient.

Reliability

The reliability of the Shuttle Walk Test has been extensively evaluated in diverse clinical settings, establishing it as an exceptionally repeatable observational measurement tool when conducted under strict standardization.

Test-Retest Reliability

The test-retest reliability of the ISWT across short intervals (1 to 7 days apart) is exceptionally high. In their seminal publication, Singh et al. (1992) established a test-retest correlation coefficient of r = 0.99 for distance walked. Subsequent systematic evaluations utilizing Intraclass Correlation Coefficients (ICC) have consistently documented ICC values ranging between 0.88 and 0.99 across elderly healthy adults, individuals with COPD, idiopathic pulmonary fibrosis, and chronic heart failure. This level of reliability indicates that systemic measurement error accounts for a negligible fraction of score variance.

The Learning Effect and Familiarization Requirements

Despite exceptional ICC values, empirical investigations uniformly identify a statistically significant and clinically relevant learning effect (practice effect) between the first (trial 1) and second (trial 2) test administrations. On average, distance walked during the second ISWT increases by 20 to 35 meters (an increment of approximately 6% to 12%) without any intervening therapeutic intervention. This enhancement is attributed to multiple psychological and neuromuscular factors:

• Reduction of situational anxiety, apprehension, and autonomic hyperarousal associated with novel testing conditions.
• Refined comprehension of the acoustic cadences and timing of turns around the turning markers.
• Optimization of stride length and motor velocity strategies to prevent premature arrival or pacing over-expenditure at each cone.
• Enhanced confidence and willingness to tolerate severe exertional sensations near maximal capacity.

Consequently, scientific guidelines published by the European Respiratory Society and American Thoracic Society (Holland et al., 2014; Singh et al., 2014) mandate that at least two practice walks be performed when establishing baseline status for research studies or rigorous clinical outcome evaluation, with the higher of the two distances recorded as the definitive baseline metric.

Inter-Rater and Intra-Rater Reliability

Inter-rater reliability of the ISWT is near-perfect (ICC > 0.98), as the test removes observer pacing bias through the standardized, prerecorded audio timing system. The observer is limited to monitoring turning compliance, tracking completed shuttles, and identifying objective termination criteria. Intra-rater reliability similarly remains exceptionally high (ICC > 0.95), provided the operational instructions, environment, and physical track parameters are held constant.

Standard Error of Measurement (SEM) and Minimal Detectable Change (MDC)

The Standard Error of Measurement (SEM) for the ISWT in cardiorespiratory populations ranges between 15.0 and 22.5 meters. Derived from the SEM, the Minimal Detectable Change (MDC at the 95% confidence level, reflecting the threshold of change required to ensure the improvement exceeds pure random measurement noise) is calculated at approximately 41.6 to 62.4 meters, a range closely paralleling the established clinical MCID of 47.5 meters.

Factor Analysis

Because the Shuttle Walk Test is an objective behavioral physical performance protocol culminating in a continuous operational score (meters walked), classical questionnaire-based factor analysis (Exploratory Factor Analysis [EFA] and Confirmatory Factor Analysis [CFA] of item-level Likert responses) does not directly apply to the shuttle count itself. However, structural psychometric analyses, Principal Component Analysis (PCA), and Structural Equation Modeling (SEM) have been deployed to delineate the latent structure of multidimensional functional capacity batteries that integrate the ISWT alongside physiological and perceptual variables.

Dimensional Structure of Physical Impairment Batteries

When the ISWT is entered into factor-analytic frameworks alongside other cardiovascular and respiratory performance metrics (such as CPET work rate, quadriceps maximum voluntary contraction torque, 6MWT distance, forced vital capacity, and arterial blood gas values), the ISWT consistently loads strongly onto a primary factor designated as Maximal Integrated Aerobic Capacity or Cardiopulmonary Exertional Reserve. Factor loadings for the ISWD on this primary exertional factor uniformly exceed λ = 0.82 to 0.89, demonstrating that the test measures systemic exercise capability rather than isolated muscular strength or isolated pulmonary mechanics.

Latent Symptom-Performance Modeling

Structural equation models examining the latent interaction between physiological variables and the terminal ISWT score demonstrate a dual-pathway architecture:

Confirmatory factor analytic fit indices for these integrated psychophysiological models demonstrate good-to-excellent structural alignment across clinical cohorts (Comparative Fit Index [CFI] > 0.95; Tucker-Lewis Index [TLI] > 0.93; Root Mean Square Error of Approximation [RMSEA] < 0.06; Standardized Root Mean Square Residual [SRMR] < 0.05). These empirical models confirm that while the terminal output of the ISWT is unidimensional (total distance in meters), the construct dynamically captures the intersection between physical aerobic reserve and psychological perceptual tolerance thresholds.

Instrument / Measurement Tool

The Shuttle Walk Test protocol must be executed under rigorous standardization in a controlled clinical environment.

Physical Track Configuration

• Course Length: A 10-meter course laid out on flat, non-slip, level indoor flooring.
• Turning Cones/Markers: Two physical markers (cones) placed on the floor inset by 0.5 meters from each end of the 10-meter course, meaning the cones are precisely 9.0 meters apart. The participant walks around the outside of the cones, thereby describing an exact 10-meter turning trajectory per shuttle.
• Corridor Dimensions: The corridor or room should be at least 12 meters in total length to provide adequate deceleration space beyond the cones, and at least 1.5 to 2.0 meters wide to allow unimpeded participant turning and clinician accompaniment if required.

Equipment and Environmental Requirements

• Standardized Audio Calibration: A standardized audio recording (originally on audio cassette/compact disc, now commonly delivered via validated digital audio platforms or software applications) containing calibrated acoustic bleeps and spoken level announcements.
• Audio Delivery System: A portable audio player or digital sound system capable of generating sufficient acoustic volume so that pacing signals are clearly audible across the course above any ambient background noise.
• Cardiorespiratory Monitoring Devices: Calibrated pulse oximeter with continuous or spot-check sensor for arterial oxygen saturation (SpO₂) and heart rate (HR), sphygmomanometer for pre- and post-test blood pressure measurement, and timer/stopwatch.
• Symptom Measurement Scales: Laminated Borg CR10 Scale boards with standardized visual anchors (from 0 = ‘Nothing at all’ to 10 = ‘Maximal / Extremely strong’) displayed before and immediately after the test.
• Safety and Resuscitation Equipment: Supplemental oxygen, rapid-acting inhaled bronchodilators, sublingual nitroglycerin, automated external defibrillator (AED), and emergency resuscitation equipment positioned near the testing course.

Protocol Progression Structure

The test comprises 12 discrete incremental levels lasting 1 minute each, yielding a cumulative total of 1020 meters (102 completed shuttles) if fully completed:

• Level 1: 3 shuttles (30 m total) — Walking speed: 0.50 m/s (1.80 km/h) — 20.00 seconds per shuttle
• Level 2: 4 shuttles (40 m total) — Walking speed: 0.67 m/s (2.41 km/h) — 15.00 seconds per shuttle
• Level 3: 5 shuttles (50 m total) — Walking speed: 0.84 m/s (3.02 km/h) — 12.00 seconds per shuttle
• Level 4: 6 shuttles (60 m total) — Walking speed: 1.01 m/s (3.64 km/h) — 9.90 seconds per shuttle
• Level 5: 7 shuttles (70 m total) — Walking speed: 1.18 m/s (4.25 km/h) — 8.47 seconds per shuttle
• Level 6: 8 shuttles (80 m total) — Walking speed: 1.35 m/s (4.86 km/h) — 7.41 seconds per shuttle
• Level 7: 9 shuttles (90 m total) — Walking speed: 1.52 m/s (5.47 km/h) — 6.58 seconds per shuttle
• Level 8: 10 shuttles (100 m total) — Walking speed: 1.69 m/s (6.08 km/h) — 5.92 seconds per shuttle
• Level 9: 11 shuttles (110 m total) — Walking speed: 1.86 m/s (6.70 km/h) — 5.38 seconds per shuttle
• Level 10: 12 shuttles (120 m total) — Walking speed: 2.03 m/s (7.31 km/h) — 4.93 seconds per shuttle
• Level 11: 13 shuttles (130 m total) — Walking speed: 2.20 m/s (7.92 km/h) — 4.55 seconds per shuttle
• Level 12: 14 shuttles (140 m total) — Walking speed: 2.37 m/s (8.53 km/h) — 4.22 seconds per shuttle

Termination Criteria

The operator ceases the assessment immediately upon manifestation of either operator-determined or participant-determined termination criteria:

• Operator Criteria (Failure to Maintain Pace): The participant fails to reach the cone (be within 0.5 meters of the marker) when the acoustic bleep sounds on two consecutive shuttles. (On the first failure, the operator issues a standardized verbal prompt: “You must speed up to reach the cone on the bleep.” If the participant fails on the very next shuttle, the test is ended immediately).
• Participant Criteria (Symptom Limitation): The participant indicates that they are too breathless or too physically fatigued to continue.
• Medical / Clinical Stop Criteria: Significant acute clinical distress, including: ischemic chest pain, acute dizziness/lightheadedness, mental confusion, sudden pallor or diaphoresis, severe claudication, profound oxygen desaturation (typically SpO₂ falling below 80% or 85% as dictated by institutional protocols), or lower extremity musculoskeletal failure.

Scoring Metrics

• Incremental Shuttle Walking Distance (ISWD): The primary outcome variable, measured in absolute meters (total number of completed 10-meter shuttles × 10). If a participant terminates mid-shuttle, only fully completed 10-meter lengths are counted.
• Peak Physiological Responses: Peak Heart Rate (bpm and % predicted), minimum nadir SpO₂ (%), and post-exercise Blood Pressure (mmHg).
• Perceptual Ratings: Pre- and post-test Borg CR10 Dyspnea score and Borg CR10 Leg Fatigue score.
• Estimated Peak VO₂: Calculated using the classic Singh et al. predictive formula: Estimated VO₂peak (mL/kg/min) = 4.19 + (0.025 × ISWD in meters).

Permissions & Fee and Test Year

The Incremental Shuttle Walk Test was first published in 1992 in the peer-reviewed medical journal Thorax by Sally J. Singh and colleagues. The Dutch clinical translation and cardiopulmonary rehabilitation integration were standardized under the Royal Dutch Society for Physical Therapy (Koninklijk Nederlands Genootschap voor Fysiotherapie – KNGF) in 2011.

The clinical test protocol, track setup, and scientific principles behind the ISWT are published in the public domain and may be reproduced and implemented freely for clinical and non-commercial academic research without royalty fees. However, the standardized, calibrated audio recording—which includes precise temporal cadence intervals, background timing tracks, and certified vocal instructions—is intellectual property owned and copyrighted by the Department of Respiratory Medicine, University Hospitals of Leicester NHS Trust, United Kingdom. Clinical practices, academic clinical trials, and rehabilitation departments seeking the official audio recordings, official instruction manual, and scoring software are required to acquire the authorized materials through the Pulmonary Rehabilitation Department at Glenfield Hospital, University Hospitals of Leicester NHS Trust (www.uhl-tr.nhs.uk). Administrative fees for purchasing official CDs, digital USB media, or software application licenses are nominal and offset maintenance, production, and clinical trial standardization costs.

References

• Borg, G. (1982). Psychophysical bases of perceived exertion. Medicine and Science in Sports and Exercise, 14(5), 377–381. https://doi.org/10.1249/00005768-198205000-00012
• Holland, A. E., Spruit, M. A., Troosters, T., Puhan, M. A., Pepin, V., Saey, D., McCormack, M. C., Carlin, B. W., Sciurba, F. C., Pitta, F., Wanger, J., MacIntyre, N., Kaminsky, D. A., Culver, B. H., Revill, S. M., Hernandes, N. A., Andrianopoulos, V., Camillo, C. A., Mitchell, K. E., … Singh, S. J. (2014). An official European Respiratory Society/American Thoracic Society technical standard: Field walking tests in chronic respiratory disease. European Respiratory Journal, 44(6), 1428–1446. https://doi.org/10.1183/09031936.00150314
• Koninklijk Nederlands Genootschap voor Fysiotherapie (KNGF). (2011). KNGF-richtlijn Hartrevalidatie. KNGF-Richtlijnen, Amersfoort, The Netherlands.
• Léger, L. A., & Lambert, J. (1982). A maximal multistage 20-m shuttle run test to predict VO2 max. European Journal of Applied Physiology and Occupational Physiology, 49(1), 1–12. https://doi.org/10.1007/BF00428958
• Lewis, M. E., Newall, C., Townend, J. N., Hill, S. L., & Bonser, R. S. (2001). Incremental shuttle walk test in addressing the suitability of heart failure patients for cardiac transplantation. Heart, 86(3), 340–344. https://doi.org/10.1136/hrt.86.3.340
• Morales, F. J., Montemayor, T., & Martinez, A. (1999). Shuttle walk test for assessment of functional capacity in chronic heart failure. American Heart Journal, 138(2), 291–298. https://doi.org/10.1016/S0002-8703(99)70114-6
• Revill, S. M., Morgan, M. D., Singh, S. J., Williams, J., & Hardman, A. E. (1999). The endurance shuttle walk: A new field test for the assessment of endurance capacity in chronic obstructive pulmonary disease. Thorax, 54(3), 213–222. https://doi.org/10.1136/thx.54.3.213
• Singh, S. J., Morgan, C. A., Scott, S., Walters, D., & Hardman, A. E. (1992). Development of a shuttle walking test of disability in patients with chronic airways obstruction. Thorax, 47(12), 1019–1024. https://doi.org/10.1136/thx.47.12.1019
• Singh, S. J., Jones, P. W., Evans, R., & Morgan, M. D. (2008). Minimum clinically important improvement for the incremental shuttle walking test. Thorax, 63(9), 775–777. https://doi.org/10.1136/thx.2007.081273
• Singh, S. J., Puhan, M. A., Andrianopoulos, V., Hernandes, N. A., Mitchell, K. E., Hill, C. J., Lee, A. L., Camillo, C. A., Troosters, T., Spruit, M. A., Carlin, B. W., Casaburi, R., … Holland, A. E. (2014). An official systematic review of the European Respiratory Society/American Thoracic Society: Measurement properties of field walking tests in chronic respiratory disease. European Respiratory Journal, 44(6), 1447–1478. https://doi.org/10.1183/09031936.00150414

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