An interventional study of A-STEP and A-STEP (New Protocol) in Cystic Fibrosis, Fibrosis and Lung Diseases, sponsored by The Alfred. Completed at 1 site in Australia. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-08-11.
Sponsored by The Alfred · Not applicable, Interventional, and Basic science
Exercise testing has become clinically important in the management and ongoing evaluation of patients with Cystic Fibrosis (CF) with higher rates of exercise tolerance and participation previously linked to lower mortality risk (1).
Lower exercise capacity generally correlates with more severe lung disease (2,3) and landmark studies suggest that low exercise capacity as measured by peak oxygen capacity (VO2peak) and rate of decline in lung function (FEV1) are strong predictors of mortality (1,4). However not all studies have found pulmonary function tests (PFTs) to be reliable predictors of maximal exercise capacity (5), especially in relatively well preserved lung function (6,7).
The wide distribution in physical capacity between fit individuals and end stage disease adds to complexity of assessment. Independent factors of age, genetics, habitual exercise, nutritional status and musculoskeletal conditions are all known to influence physical capacity in patients with CF (8,9).
Maximal exercise testing places additional stress on cardiovascular, respiratory and peripheral systems providing more information around multiple influences on disease progression including degree of limitation in these major systems (10,11) and is useful for assessment of exercise desaturation, more common (but not always present) in advanced lung disease (5,12).
With prediction of exercise performance and functional capacity from PFTs unreliable and the understanding that health status correlates better with exercise tolerance there has been an increase in maximal exercise testing for patient management (13). Many international centers now regard exercise testing as highly important with many assessing maximal exercise capacity annually to monitor disease progression, identify physical status and drive changes in medical, physiotherapy or nutritional management (14,15).
The main vision is to develop a standardized incremental step test protocol suitable for adults with Cystic Fibrosis (CF), all ages, levels of fitness and disease state that is in line with current exercise testing recommendations (15). To develop a more useful field test to assess exercise tolerance and a more "user friendly" test than the currently available laboratory exercise test to allow for early detection of decline in physical function in the day-to-day clinical setting. To date no studies have been published in adults with CF where an incremental exercise step test has been investigated to assess exercise tolerance or determine maximum oxygen uptake (VO2max).
Many international centers now regard exercise testing as highly important with many measuring maximal exercise capacity annually to monitor disease progression, identify physical status and to drive changes in medical, physiotherapy or nutritional management (14,15).
Cardiopulmonary Exercise Testing (CPET):
The current best practice for assessing VO2max in adults with CF is a CPET using the Godfrey Protocol, a progressive and incremental maximal test performed on a cycle ergometer (13,14,15). Exercise testing should aim to achieve a maximal response within a time frame of 8-12 min and incremental protocols with stage duration of 1 minute are considered more efficient in eliciting the desired response within this time frame (14). During CPET, VO2max is determined while breath-by-breath gas analysis allows for a comprehensive assessment of exercise ventilation and circulation. This information can identify reasons for low exercise capacity and whether exercise limitation is due to deconditioning, or primarily within the respiratory, cardiovascular or peripheral systems. CPET is performed using a specialist ergometer, and requires specialist clinical expertise, monitoring and reporting equipment for interpretation of the test. The cost, space and expertise to carry out CPET in CF units around the world may limit its use for the regular assessment of exercise capacity in adults with CF (16).
Field Tests:
Field tests generally cannot determine absolute maximal exercise capacity, but do provide valuable information about the patient's functional abilities and limitations and compared to laboratory tests are inexpensive and easy to administer.
Field tests that use a single step for assessment of exercise tolerance in patients with chronic lung disease include:
3-Minute Step Test (3MST):
The 3MST is a feasible and acceptable measure of sub-maximal exercise performance in children and adults and a useful tool in the assessment of oxygen desaturation (17,18). The test is short in duration, simple to carry out, and has low cost and minimal space and equipment requirements however the sub-maximal nature and ceiling effect of the 3MST limits its usefulness clinically across the age spectrum (18,19).
The Chester Step Test (CST):
The CST is a 10-minute sub-maximal standardized multistage test and like the 3MST has minimal space and equipment requirements. The CST was originally designed for workplace screening and is now widely used for exercise prescription in the UK cardiac population (20). In healthy individuals one study reported a ceiling effect and a positive relationship between predicted VO2max using the CST and measured VO2max (21) however a subsequent study questioned this prediction validity (22). The CST has been found to be highly reproducible in patients with chronic obstructive lung disease (COPD) and reliable in patients with Bronchiectasis, but too challenging for both groups (23,24).
The Modified Incremental Step Test (MIST):
The MIST was designed to be more suitable for COPD patients and modeled from the CST(25). A reduction in work rate was not found to result in a difference in cardiopulmonary stress and exertion effort at peak exercise but did result in a higher exercise tolerance in patients with COPD. The MIST is reliable and better tolerated than the CST in patients with Bronchiectasis (23,24).
The CST and CF:
One study (published in abstract form) has shown the CST to be a useful field test when compared to the 3MST and 6MWT for those with mild to moderate CF. The authors commented this was likely due to the progressive nature being more representative of adult physical activity (26).
The main vision is to develop a standardized incremental step test protocol suitable for adults with Cystic Fibrosis (CF), all ages, levels of fitness and disease state that is in line with current exercise testing recommendations (15). The test should be a more useful than the already available field tests and more "user friendly" test than the currently available laboratory exercise test to assess exercise tolerance and allow for early detection of decline in physical function in the day-to-day clinical setting. To date no studies have been published in adults with CF where an incremental exercise step test has been investigated to assess exercise tolerance or determine VO2max.
To design a standardized externally paced incremental step test that is portable, easy to administer, simple to perform, time, cost and space efficient (A-STEP).
Study A:
To determine if the A-STEP is a more useful tool than the 3-Minute Step Test.
Study B:
The principle investigator hypothesizes that the A-STEP will be a feasible tool to assess exercise capacity; and the A-STEP max will be a valid tool for the assessment of VO2max across the age range and disease spectrum in adults with CF.
1,581 studies on the registry are indexed under Cystic Fibrosis; 190 are open to participants now.
This study's enrollment of 7 is below the median of 36 across 1,034 interventional studies indexed under Cystic Fibrosis.
Browse Cystic Fibrosis studies →The Alfred is the lead sponsor of 45 studies on the registry; 4 are open to participants now.
Counted across the registry records on this site, refreshed daily.
EXCLUSION
(ATS/ACCP 2003; Hebestreit 2015)
Study A) A-STEP Study Development of new exercise test protocol and Observational Feasibility/Safety Study (no comparator).
Other: A-STEP
Study B) A-STEPmax Study Validity Study (random allocation of test order).
Other: A-STEP (New Protocol)
Study B) A-STEPmax Study Validity Study (random allocation of test order).
Other: Comparator: CPET cycle ergometer (Gold Standard)
Study A) Study A) Development of new exercise test protocol and Observational Feasibility/Safety Study (no comparator). Feasibility/safety of a newly designed, incremental, maximal, standardised step test in adults with Cystic Fibrosis.
Also known as: Alfred Step Test Exercise Protocol (A-STEP)
Study B) Validation Study (random allocation of test order). Validity of an incremental, maximal, standardised incremental step test with breath-by-breath gas analysis using portable metabolic measurement equipment against CPET.
Also known as: Alfred Step Test Exercise Protocol
Study B) Validation study (random allocation of test order) "Gold standard" CPET. An incremental, maximal standardised cycle ergometer exercise test (performed as per published protocol) using portable metabolic measurement equipment.
Also known as: Cardiopulmonary Exercise Test Protocol
Study B) Maximum oxygen uptake (VO2max)
The highest oxygen uptake achieved during the exercise test taken from inspired gas in a given period of time. Body weight is used to calculate this from oxygen consumption during the test. VO2peak may be used as a surrogate if VO2max is not achieved. Criteria for reaching maximum effort is not included in this document.
Time frame: Measured during the incremental test for a maximum of 15 minutes.
Study A) Oxygen Saturation
Standard objective outcome measures of field exercise testing. Measured via pulse oximetry.
Time frame: Measured for 3 min prior to exercise (recorded at baseline sitting and standing), monitored during the test (recorded at minute intervals) and for at least 2 min of recovery up to a maximum of 10 minutes.
Study A) Heart Rate
Standard objective outcome measures of field exercise testing. Measured via pulse oximetry.
Time frame: Measures for 3 min prior to exercise (recorded at baseline sitting and standing), monitored during the test (recorded at minute intervals) and for at least 2 min of recovery up to a maximum of 10 minutes.
Study B) Carbon Dioxide Production
Standard secondary outcome measure of maximal exercise testing using breath- by-breath gas analysis with portable metabolic measurement equipment.
Time frame: Measured during the test incremental tests for a maximum 15 minutes and 5 mins of recovery.
Study B) Respiratory Exchange Ratio
Standard secondary outcome measure of maximal exercise testing using breath- by-breath gas analysis. The ratio of carbon dioxide production to oxygen consumption.
Time frame: Measured during the test incremental tests for a maximum 15 minutes and 5 mins of recovery.
Study B) Minute Ventilation
Standard secondary outcome measure of maximal exercise testing using breath- by-breath gas analysis. The product of tidal volume and respiratory rate.
Time frame: Measured during the test incremental tests for a maximum 15 minutes and 5 mins of recovery.
Study B) Oxygen Pulse
Standard secondary outcome measure of maximal exercise testing using breath- by-breath gas analysis. Calculated by dividing the oxygen consumption by heart rate.
Time frame: Measured during the test incremental tests for a maximum 15 minutes and 5 mins of recovery.
Study B) Tidal Volume
Standard secondary outcome measure of maximal exercise testing using breath- by-breath gas analysis. The volume of each breath taken.
Time frame: Measured during the test incremental tests for a maximum 15 minutes and 5 mins of recovery.
Study B) Oxygen Saturation
Standard objective outcome measures of exercise testing. Measured via pulse oximetry.
Time frame: easures are taken at baseline (post 5 mins), monitored during the test (recorded at minute intervals) and for min 5 mins of recovery
Study B) Heart rate
Standard objective outcome measures of exercise testing. Measured via pulse oximetry.
Time frame: easures are taken at baseline (post 5 mins), monitored during the test (recorded at minute intervals) and for min 5 mins of recovery
Study B) Measures from Electrocardiogram
Used to monitor the patient's cardiac rhythm (CPET only)
Time frame: easures are taken at baseline (post 5 mins), monitored during the test (recorded at minute intervals) and for min 5 mins of recovery
Study A & B) Breathlessness and Leg Fatigue
Standard subjective outcome measures of exercise testing. Modified Borg 0-10.
Time frame: Measures are taken at baseline (post 5 mins), monitored during the test (recorded at minute intervals) and for min 5 mins of recovery
Study A & B) Blood pressure
Standard outcome measure of exercise testing.
Time frame: Measures are takenpre/post A-STEP, pre/every 2 mins during/post CPET
Study A & B) Duration of test; Highest level (mins and sec)/stage achieved; Reason for test termination.
Parameters of exercise test.
Time frame: Measured during or on completion of the test. Maximum 15 minutes.
Study A & B) Gender; Age, Height, BMI, fitness level
Demographic baseline descriptive measures.
Time frame: Recorded on the day of testing maximum 10 mins.
Study A & B) Spirometry (Pulmonary Function Tests)
Baseline Pulmonary Function Test measures.
Time frame: Recorded on the day of testing prior to testing, maximum 10 minutes Study B. Most recent PFTs if day of testing lung function is not available study A.
Study A & B) Alfred Wellness Score for CF (AweScore CF)
Alfred specific clinical tools: quality of life measure.
Time frame: Recorded on the day of testing prior to testing, maximum 2 minutes.
Study A) Musculoskeletal Assessment Tool-Quick Screen
Alfred specific clinical tool: to screen for musculoskeletal issues.
Time frame: Recorded on the day of testing, maximum 20 minutes.
Study A & B) Medical history.
Baseline descriptive measures of health status.
Time frame: Recorded on the day of testing, maximum 10 minutes.
Plan to share: No — No plan to share individual patient data.
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