Effects of a Walking Program and Inspiratory Muscle Training in Individuals With Chronic Heart Failure

• Sponsor: Texas Woman's University (Other)
• Overall Status: Completed
• CT.gov ID: NCT01560871
• Collaborator: Texas Health Resources (Other)
• Enrollment: 16
• Locations: 2
• Arms: 2
• Duration (Months): 70
• Patients Per Site: 8
• Patients Per Site Per Month: 0.1

Study Details

Study Description

Brief Summary

Individuals with chronic heart failure need a "safe and effective" exercise program that could enhance their quality of life. In this study, we examined whether an experimental exercise program of autonomous walking and high-intensity Inspiratory Muscle Training (IMT) could result in better effects on respiratory muscle strength (PImax), cardiovascular endurance, quality of life, and physical activity, when compared to autonomous walking and "sham" IMT program, in adults with chronic heart failure.

Condition or Disease	Intervention/Treatment	Phase
Heart Failure NYHA Class II; Heart Failure NYHA Class III	Behavioral: High-intensity IMT plus walking; Behavioral: Low-intensity IMT plus walking	N/A

Detailed Description

Participants were recruited from the outpatient heart failure transitional care clinic at the Presbyterian Hospital of Dallas and other local heart failure support groups. Flyers were distributed to cardiologists, nurse practitioners, and local heart failure support groups in the Dallas/Ft Worth area. Cardiologists and nurse practitioners were aware of the scope of the study and its inclusion and exclusion criteria of research participants. Potential research participants could then call the research team for further information.

Participants came to our facility for the initial evaluation session, where a history interview was conducted to gather demographic data, such as age, gender, height, weight, race/ethnicity, and past medical/surgical history. The following baseline data were then collected: a) two trials of the six-minute walk test, b) respiratory muscle strength indicated by maximal inspiratory pressure (PImax), and two quality of life questionnaires. During the walk test, heart rate and heart rhythms were continuously monitored via a holter monitor. During the rest breaks, research participants filled out two quality of life questionnaires (SF-36, Minnesota Living with Heart Failure Questionnaire).

Each participant was randomly assigned to one of the two groups: a) the autonomous walking program with a high-intensity Inspiratory Muscle Training (IMT) program, or b) the autonomous walking program with a sham IMT. The training threshold for the experimental IMT group was trained at 60%PImax which was reassessed at weekly follow ups. The frequency of training was 5x/week (1x/day preferred) for 6 interval levels at each session (6 inspiratory efforts in each level): (1) 60s rest interval; (2) 45s rest interval; (3) 30s rest interval; (4) 15s rest interval; (5)10s rest interval; (6) 5s rest interval, trained to exhaustion. The intensity of sham IMT was set at fixed 15% PImax. Research participants were blinded to the group assignment. The time commitment for IMT was about 15-20 minutes a session per day at home. Weekly follow up was conducted at the School of Physical Therapy in Dallas to reassess PImax, collect the log of daily step count, and discuss about the walking program. Every participant was given a breathing device for inspiratory muscle training.

Each participant was given a pedometer and a heart rate monitor to track their daily step counts and heart rate during the walking session. The walking program consisted of walking daily at an intensity of "somewhat hard" to "hard" on the Borg's Rating of Perceived Exertion (RPE) scale. Participants were encouraged to walk 10 to 15 minutes, once to twice a day initially, then progressed to about 45-50 minutes a day by week six, if they could tolerate. At the end of 6 weeks, these participants returned to our facility for the final evaluation session.

Study Design

• Study Type: Interventional
• Actual Enrollment: 16 participants
• Allocation: Randomized
• Intervention Model: Parallel Assignment
• Masking: Double (Participant, Outcomes Assessor)
• Primary Purpose: Treatment
• Official Title: Effects of a Walking Program and Inspiratory Muscle Training in Individuals With Chronic Heart Failure - A Pilot Study
• Study Start Date: Mar 1, 2012
• Actual Primary Completion Date: Jan 1, 2018
• Actual Study Completion Date: Jan 1, 2018

Arms and Interventions

Arm	Intervention/Treatment
Sham Comparator: Low-intensity IMT Plus Walking Inspiratory Muscle Training (IMT) intensity was set at 15% PImax. The walking program consisted of walking every day at an intensity of "somewhat hard" to "hard" on the Borg's Rating of Perceived Exertion (RPE) scale. Participants were encouraged to walk at 10 to 15 minutes, once to twice a day initially, then progressed to 45-50 minutes a day by the end of the six weeks, if they could tolerate.	Behavioral: Low-intensity IMT plus walking; The IMT training was 3 sets of 10 repetitions, or when the participant felt tired. Participants returned to our facility every week to reassess PImax. For the walking program, each participant was given a pedometer and a heart rate monitor to track daily step counts and heart rate. The walking program consisted of walking every day at an intensity of "somewhat hard" to "hard" on the Borg's Rating of Perceived Exertion scale. Participants began at least 10 to 15 minutes, once to twice a day, for 7 days a week, and eventually progressed to 45-50 minutes a day by the end of the six weeks, if they could tolerate.
Experimental: High-intensity IMT Plus Walking Inspiratory Muscle Training (IMT) intensity was set at 60% PImax. The walking program was the same as the one for the control group.	Behavioral: High-intensity IMT plus walking; The IMT intensity was set at 60% of PImax which was reassessed weekly. Frequency: 5x/week; 1x/day preferred. 6 Interval Levels: (6 efforts at each level): (1) 60s rest interval; (2) 45s rest interval; (3) 30s rest interval; (4) 15s rest interval; (5)10s rest interval; (6) 5s rest interval, trained to exhaustion. For the walking program, it was the same as the one for the control group.

Outcome Measures

Primary Outcome Measures

1. Change From Baseline in Mean Minnesota Living With Heart Failure Questionnaire Score [Baseline and 6 weeks]

   This questionnaire includes 21 questions which ask how much the heart condition affected the patient's life during the past month. Each question has 5 optional answers with the scores ranging from 0 to 5. A higher score indicates a worse outcome. The minimum overall score of the questionnaire is 0 and the maximum score is 105. A higher overall score on the Minnesota Living with Heart Failure Questionnaire indicates a worse outcome.

2. Change From Baseline in Mean Score of Physical Component of the SF-36 Questionnaire [Baseline and 6 weeks]

   The SF-36 quality of life questionnaire (short form) was used. A higher score of the SF-36 questionnaire indicates a better outcome (i.e., lower disability). The range of overall score on the SF-36 questionnaire is from 0 to 100.

Secondary Outcome Measures

1. Mean Daily Step Counts From Week 1 to Week 6 [Baseline and 6 weeks]

   Each subject was given a pedometer to record his/her step counts every day.

2. Respiratory Muscle Strength is Indicated by Maximal Inspiratory Pressure (PImax) [Baseline and 6 weeks]

   The inspiratory muscle strength will be measured in the unit of cmH2O by the Respiratory Muscle Pressure Meter (Micro Direct). A higher inspiratory pressure indicates a better inspiratory breathing strength.

3. Six-minute Walk Test Distance [Baseline and 6 Weeks]

   The six-minute walk test is a measure of cardiovascular endurance which measures how far a person can walk in 6 minutes. This test was conducted twice respectively at pre-training and at post-training to account for potential learning effect. A longer distance walked on the six-minute walking test indicates a better cardiovascular endurance.

Eligibility Criteria

Criteria

• Ages Eligible for Study: 18 Years to 90 Years
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: No

Inclusion Criteria:

• adults with chronic heart failure (NYHA Functional Class II-III)

• BMI < 35 kg/m^2

• Age: 18 to 90 years

• walk independently with or without an assisted device

• hospital discharge for CHF within a year.

Exclusion Criteria:

• ECG with uncontrolled ventricular arrhythmia

• bronchiectasis

• limited walking ability due to neurologic or orthopedic impairments of the legs

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Outpatient heart failure transitional care clinic, Presbyterian Hospital of Dallas, Texas Health Resources	Dallas	Texas	United States	75231
2	School of Physical Therapy, Texas Woman's University	Dallas	Texas	United States	75235

Sponsors and Collaborators

• Texas Woman's University
• Texas Health Resources

Investigators

• Principal Investigator: Suh-Jen Lin, PhD, PT, Texas Woman's University

Study Documents (Full-Text)

• Informed Consent Form - Mar 14, 2017
• Study Protocol and Statistical Analysis Plan - Dec 2, 2013

More Information

Publications

• Bailly L, Mossé P, Diagana S, Fournier M, d'Arripe-Longueville F, Diagana O, Gal J, Grebet J, Moncada M, Domerego JJ, Radel R, Fabre R, Fuch A, Pradier C. "As du Coeur" study: a randomized controlled trial on quality of life impact and cost effectiveness of a physical activity program in patients with cardiovascular disease. BMC Cardiovasc Disord. 2018 Dec 6;18(1):225. doi: 10.1186/s12872-018-0973-3.
• Borg GA. Psychophysical bases of perceived exertion. Med Sci Sports Exerc. 1982;14(5):377-81.
• Gheorghiade M, Vaduganathan M, Fonarow GC, Bonow RO. Rehospitalization for heart failure: problems and perspectives. J Am Coll Cardiol. 2013 Jan 29;61(4):391-403. doi: 10.1016/j.jacc.2012.09.038. Epub 2012 Dec 5.
• Lin SJ, McElfresh J, Hall B, Bloom R, Farrell K. Inspiratory muscle training in patients with heart failure: a systematic review. Cardiopulm Phys Ther J. 2012 Sep;23(3):29-36.
• Marco E, Ramírez-Sarmiento AL, Coloma A, Sartor M, Comin-Colet J, Vila J, Enjuanes C, Bruguera J, Escalada F, Gea J, Orozco-Levi M. High-intensity vs. sham inspiratory muscle training in patients with chronic heart failure: a prospective randomized trial. Eur J Heart Fail. 2013 Aug;15(8):892-901. doi: 10.1093/eurjhf/hft035. Epub 2013 Mar 19.
• Middel B, Bouma J, de Jongste M, van Sonderen E, Niemeijer MG, Crijns H, van den Heuvel W. Psychometric properties of the Minnesota Living with Heart Failure Questionnaire (MLHF-Q). Clin Rehabil. 2001 Oct;15(5):489-500.
• Neder JA, Andreoni S, Lerario MC, Nery LE. Reference values for lung function tests. II. Maximal respiratory pressures and voluntary ventilation. Braz J Med Biol Res. 1999 Jun;32(6):719-27.
• Rector TS, Cohn JN. Assessment of patient outcome with the Minnesota Living with Heart Failure questionnaire: reliability and validity during a randomized, double-blind, placebo-controlled trial of pimobendan. Pimobendan Multicenter Research Group. Am Heart J. 1992 Oct;124(4):1017-25.
• Tudor-Locke C, Craig CL, Brown WJ, Clemes SA, De Cocker K, Giles-Corti B, Hatano Y, Inoue S, Matsudo SM, Mutrie N, Oppert JM, Rowe DA, Schmidt MD, Schofield GM, Spence JC, Teixeira PJ, Tully MA, Blair SN. How many steps/day are enough? For adults. Int J Behav Nutr Phys Act. 2011 Jul 28;8:79. doi: 10.1186/1479-5868-8-79. Review.
• Tudor-Locke C, Hart TL, Washington TL. Expected values for pedometer-determined physical activity in older populations. Int J Behav Nutr Phys Act. 2009 Aug 25;6:59. doi: 10.1186/1479-5868-6-59. Erratum in: Int J Behav Nutr Phys Act. 2009 Oct 09;6:65.
• Van Spall HGC, Lee SF, Xie F, Oz UE, Perez R, Mitoff PR, Maingi M, Tjandrawidjaja MC, Heffernan M, Zia MI, Porepa L, Panju M, Thabane L, Graham ID, Haynes RB, Haughton D, Simek KD, Ko DT, Connolly SJ. Effect of Patient-Centered Transitional Care Services on Clinical Outcomes in Patients Hospitalized for Heart Failure: The PACT-HF Randomized Clinical Trial. JAMA. 2019 Feb 26;321(8):753-761. doi: 10.1001/jama.2019.0710.

• Responsible Party: Suh-Jen Lin, Associate Professor, Texas Woman's University
• ClinicalTrials.gov Identifier: NCT01560871
• Other Study ID Numbers: 16969
• First Posted: Mar 22, 2012
• Last Update Posted: Apr 3, 2020
• Last Verified: Apr 1, 2020

• Keywords provided by Suh-Jen Lin, Associate Professor, Texas Woman's University: Heart failure; inspiratory muscle training; physical activity
• Additional relevant MeSH terms: Respiratory Aspiration; Heart Failure

Study Results

Participant Flow

Arm/Group Title	Low-intensity IMT Plus Walking	High-intensity IMT Plus Walking
Arm/Group Description	Inspiratory Muscle Training (IMT) intensity is set at 15% PImax. The walking program consists of walking daily at an intensity of "somewhat hard" to "hard" on the Rating of Perceived Exertion scale. Participants are encouraged to walk 15 minutes twice a day, then progress to 45-50 minutes a day by six weeks. Low-intensity IMT plus walking: The IMT training is about 15-20 minutes. Both groups will need to come in once a week for 15 to 20 minutes to probably readjust the IMT training intensity on the breathing device. For the walking program, each participant will be given a pedometer and a heart rate monitor so he/she can track daily step counts and walking heart rate during the study. The walking program will consist of walking every day at an intensity of "hard" to "somewhat hard" on the Rating of Perceived Exertion (RPE) scale. Participants will begin walking at least 15 minutes twice a day for 7 days a week and eventually pr	Inspiratory Muscle Training (IMT) intensity is set at 60% PImax. The walking program will consist of walking daily at an intensity of "somewhat hard" to "hard" on the Rating of Perceived Exertion scale. Participants are encouraged to walk 15 minutes twice a day initially, then progress to 45-50 minutes a day by six weeks. High-intensity IMT plus walking: The IMT intensity will be set at 60% of PImax which will be adjusted weekly and nose clip will be used. Frequency: 5x/week; 1x/day preferred. 6 Interval Levels: (6 efforts at each level): (1) 60s rest interval; (2) 45s rest interval; (3) 30s rest interval; (4) 15s rest interval; (5)10s rest interval; (6) 5s rest interval, trained to exhaustion. For the walking program, each participant will be given a pedometer and a heart rate monitor so he/she can track daily step counts and heart rate during the study. The walking program will consist of walking every day at an intensity of "hard" to "somewhat har
Period Title: Overall Study
STARTED	9	7
COMPLETED	3	5
NOT COMPLETED	6	2

Baseline Characteristics

Arm/Group Title	Low-intensity IMT Plus Walking	High-intensity IMT Plus Walking	Total
Arm/Group Description	Inspiratory Muscle Training (IMT) intensity is set at 15% PImax. The walking program will consist of walking every day at an intensity of "hard" to "somewhat hard" on the Rating of Perceived Exertion (RPE) scale. Participants will be instructed to walk at 15 minutes twice a day initially, then progress to 45-50 minutes a day by the end of the six weeks. Low-intensity IMT plus walking: The IMT training is about 15-20 minutes. Both groups will need to come in once a week for 15 to 20 minutes to probably readjust the IMT training intensity on the breathing device. For the walking program, each participant will be given a pedometer and a heart rate monitor so he/she can track daily step counts and walking heart rate during the study. The walking program will consist of walking every day at an intensity of "hard" to "somewhat hard" on the Rating of Perceived Exertion (RPE) scale. Participants will begin walking at least 15 minutes twice a day for 7 days a week and eventually pr	Inspiratory Muscle Training (IMT) intensity is set at 60% PImax. The walking program will consist of walking every day at an intensity of "hard" to "somewhat hard" on the Rating of Perceived Exertion (RPE) scale. Participants will be instructed to walk 15 minutes twice a day initially, then progress to 45-50 minutes a day by the end of six weeks. High-intensity IMT plus walking: The IMT intensity will be set at 60% of PImax which will be adjusted weekly and nose clip will be used. Frequency: 5x/week; 1x/day preferred. 6 Interval Levels: (6 efforts at each level): (1) 60s rest interval; (2) 45s rest interval; (3) 30s rest interval; (4) 15s rest interval; (5)10s rest interval; (6) 5s rest interval, trained to exhaustion. For the walking program, each participant will be given a pedometer and a heart rate monitor so he/she can track daily step counts and heart rate during the study. The walking program will consist of walking every day at an intensity of "hard" to "somewhat har	Total of all reporting groups
Overall Participants	9	7	16
Age (Count of Participants)
<=18 years	0 0%	0 0%	0 0%
Between 18 and 65 years	7 77.8%	7 100%	14 87.5%
>=65 years	2 22.2%	0 0%	2 12.5%
Sex: Female, Male (Count of Participants)
Female	3 33.3%	1 14.3%	4 25%
Male	6 66.7%	6 85.7%	12 75%
Ethnicity (NIH/OMB) (Count of Participants)
Hispanic or Latino	0 0%	1 14.3%	1 6.3%
Not Hispanic or Latino	9 100%	6 85.7%	15 93.8%
Unknown or Not Reported	0 0%	0 0%	0 0%
Six-Minute Walk Test Distance (meters) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [meters]	413.92 (85)	356.00 (85.3)	388 (109)

Outcome Measures

1. Primary Outcome

Title	Change From Baseline in Mean Minnesota Living With Heart Failure Questionnaire Score
Description	This questionnaire includes 21 questions which ask how much the heart condition affected the patient's life during the past month. Each question has 5 optional answers with the scores ranging from 0 to 5. A higher score indicates a worse outcome. The minimum overall score of the questionnaire is 0 and the maximum score is 105. A higher overall score on the Minnesota Living with Heart Failure Questionnaire indicates a worse outcome.
Time Frame	Baseline and 6 weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Low-intensity IMT Plus Walking	High-intensity IMT Plus Walking
Arm/Group Description	For the low-intensity Inspiratory Muscle Training (IMT), the intensity was set at 15% maximal inspiratory pressure (PImax), which was considered "Sham training".. The walking program consisted of walking at an intensity of "hard" to "somewhat hard" on the Borg's Rating of Perceived Exertion scale. Participants were encouraged to walk at 15 minutes once to twice a day initially, then progress to a total of 45-50 minutes a day, if they could tolerate, by the end of six weeks. Every participant was given a pedometer and a polar heart rate monitor to track step counts and walking heart rate. The IMT training is about 15-20 minutes. Both groups came to our facility once a week for 15 to 20 minutes for discussions about their progress and readjustment of the training intensity on the IMT breathing device.	For the high-intensity Inspiratory Muscle Training (IMT), the intensity is set at 60% maximal inspiratory pressure (PImax). Frequency: 5x/week; 1x/day preferred. 6 rest Interval Levels: (6 efforts at each level): (1) 60s rest interval; (2) 45s rest interval; (3) 30s rest interval; (4) 15s rest interval; (5)10s rest interval; (6) 5s rest interval, trained to exhaustion. The walking program consisted of walking at an intensity of "hard" to "somewhat hard" on the Borg's Rating of Perceived Exertion scale. Participants were encouraged to walk at 15 minutes once to twice a day initially, then progress to a total of 45-50 minutes a day, if they could tolerate, by the end of six weeks. Every participant was given a pedometer and a polar heart rate monitor to track step counts and walking heart rate. Both groups returned once a week for discussions about their progress and readjustment of the IMT training intensity based on the new PImax measured..
Measure Participants	3	5
MLHF score at baseline	36	57.6
change from baseline at 6 weeks	18.6	-20.6

2. Primary Outcome

Title	Change From Baseline in Mean Score of Physical Component of the SF-36 Questionnaire
Description	The SF-36 quality of life questionnaire (short form) was used. A higher score of the SF-36 questionnaire indicates a better outcome (i.e., lower disability). The range of overall score on the SF-36 questionnaire is from 0 to 100.
Time Frame	Baseline and 6 weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Low-intensity IMT Plus Walking	High-intensity IMT Plus Walking
Arm/Group Description	For the low-intensity Inspiratory Muscle Training (IMT), the intensity was set at 15% maximal inspiratory pressure (PImax), which was considered "Sham training".. The walking program consisted of walking at an intensity of "hard" to "somewhat hard" on the Borg's Rating of Perceived Exertion scale. Participants were encouraged to walk at 15 minutes once to twice a day initially, then progress to a total of 45-50 minutes a day, if they could tolerate, by the end of six weeks. Every participant was given a pedometer and a polar heart rate monitor to track step counts and walking heart rate. The IMT training is about 15-20 minutes. Both groups came to our facility once a week for 15 to 20 minutes for discussions about their progress and readjustment of the training intensity on the IMT breathing device.	For the high-intensity Inspiratory Muscle Training (IMT), the intensity is set at 60% maximal inspiratory pressure (PImax). Frequency: 5x/week; 1x/day preferred. 6 rest Interval Levels: (6 efforts at each level): (1) 60s rest interval; (2) 45s rest interval; (3) 30s rest interval; (4) 15s rest interval; (5)10s rest interval; (6) 5s rest interval, trained to exhaustion. The walking program consisted of walking at an intensity of "hard" to "somewhat hard" on the Borg's Rating of Perceived Exertion scale. Participants were encouraged to walk at 15 minutes once to twice a day initially, then progress to a total of 45-50 minutes a day, if they could tolerate, by the end of six weeks. Every participant was given a pedometer and a polar heart rate monitor to track step counts and walking heart rate. Both groups returned once a week for discussions about their progress and readjustment of the IMT training intensity based on the new PImax measured..
Measure Participants	3	5
Baseline Physical SF-36	34.1	30.7
Change from baseline physical SF-36	0.82	7.08

3. Secondary Outcome

Title	Mean Daily Step Counts From Week 1 to Week 6
Description	Each subject was given a pedometer to record his/her step counts every day.
Time Frame	Baseline and 6 weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Low-intensity IMT Plus Walking	High-intensity IMT Plus Walking
Arm/Group Description	For the low-intensity Inspiratory Muscle Training (IMT), the intensity was set at 15% maximal inspiratory pressure (PImax), which was considered "Sham training".. The walking program consisted of walking at an intensity of "hard" to "somewhat hard" on the Borg's Rating of Perceived Exertion scale. Participants were encouraged to walk at 15 minutes once to twice a day initially, then progress to a total of 45-50 minutes a day, if they could tolerate, by the end of six weeks. Every participant was given a pedometer and a polar heart rate monitor to track step counts and walking heart rate. The IMT training is about 15-20 minutes. Both groups came to our facility once a week for 15 to 20 minutes for discussions about their progress and readjustment of the training intensity on the IMT breathing device.	For the high-intensity Inspiratory Muscle Training (IMT), the intensity is set at 60% maximal inspiratory pressure (PImax). Frequency: 5x/week; 1x/day preferred. 6 rest Interval Levels: (6 efforts at each level): (1) 60s rest interval; (2) 45s rest interval; (3) 30s rest interval; (4) 15s rest interval; (5)10s rest interval; (6) 5s rest interval, trained to exhaustion. The walking program was the same as the one for the control group. Both groups returned once a week for discussions about their progress and readjustment of the IMT training intensity based on the new PImax measured..
Measure Participants	3	5
Baseline daily step count at Week 1	3512	7002
Daily step counts at week 6	4434	9255

4. Secondary Outcome

Title	Respiratory Muscle Strength is Indicated by Maximal Inspiratory Pressure (PImax)
Description	The inspiratory muscle strength will be measured in the unit of cmH2O by the Respiratory Muscle Pressure Meter (Micro Direct). A higher inspiratory pressure indicates a better inspiratory breathing strength.
Time Frame	Baseline and 6 weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Low-intensity IMT Plus Walking	High-intensity IMT Plus Walking
Arm/Group Description	For the low-intensity Inspiratory Muscle Training (IMT), the intensity was set at 15% maximal inspiratory pressure (PImax), which was considered "Sham training".. The walking program consisted of walking at an intensity of "hard" to "somewhat hard" on the Borg's Rating of Perceived Exertion scale. Participants were encouraged to walk at 15 minutes once to twice a day initially, then progress to a total of 45-50 minutes a day, if they could tolerate, by the end of six weeks. Every participant was given a pedometer and a polar heart rate monitor to track step counts and walking heart rate. The IMT training is about 15-20 minutes. Both groups came to our facility once a week for 15 to 20 minutes for discussions about their progress and readjustment of the training intensity on the IMT breathing device.	For the high-intensity Inspiratory Muscle Training (IMT), the intensity is set at 60% maximal inspiratory pressure (PImax). Frequency: 5x/week; 1x/day preferred. 6 rest Interval Levels: (6 efforts at each level): (1) 60s rest interval; (2) 45s rest interval; (3) 30s rest interval; (4) 15s rest interval; (5)10s rest interval; (6) 5s rest interval, trained to exhaustion. The walking program consisted of walking at an intensity of "hard" to "somewhat hard" on the Borg's Rating of Perceived Exertion scale. Participants were encouraged to walk at 15 minutes once to twice a day initially, then progress to a total of 45-50 minutes a day, if they could tolerate, by the end of six weeks. Every participant was given a pedometer and a polar heart rate monitor to track step counts and walking heart rate. Both groups returned once a week for discussions about their progress and readjustment of the IMT training intensity based on the new PImax measured..
Measure Participants	3	5
Baseline PImax at week 1	51.44	43.53
PImax at week 6	57.22	58.13

5. Secondary Outcome

Title	Six-minute Walk Test Distance
Description	The six-minute walk test is a measure of cardiovascular endurance which measures how far a person can walk in 6 minutes. This test was conducted twice respectively at pre-training and at post-training to account for potential learning effect. A longer distance walked on the six-minute walking test indicates a better cardiovascular endurance.
Time Frame	Baseline and 6 Weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Low-intensity IMT Plus Walking	High-intensity IMT Plus Walking
Arm/Group Description	For the low-intensity Inspiratory Muscle Training (IMT), the intensity was set at 15% maximal inspiratory pressure (PImax), which was considered "Sham training".. The walking program consisted of walking at an intensity of "hard" to "somewhat hard" on the Borg's Rating of Perceived Exertion scale. Participants were encouraged to walk at 15 minutes once to twice a day initially, then progress to a total of 45-50 minutes a day, if they could tolerate, by the end of six weeks. Every participant was given a pedometer and a polar heart rate monitor to track step counts and walking heart rate. The IMT training is about 15-20 minutes. Both groups came to our facility once a week for 15 to 20 minutes for discussions about their progress and readjustment of the training intensity on the IMT breathing device.	For the high-intensity Inspiratory Muscle Training (IMT), the intensity is set at 60% maximal inspiratory pressure (PImax). Frequency: 5x/week; 1x/day preferred. 6 rest Interval Levels: (6 efforts at each level): (1) 60s rest interval; (2) 45s rest interval; (3) 30s rest interval; (4) 15s rest interval; (5)10s rest interval; (6) 5s rest interval, trained to exhaustion. The walking program consisted of walking at an intensity of "hard" to "somewhat hard" on the Borg's Rating of Perceived Exertion scale. Participants were encouraged to walk at 15 minutes once to twice a day initially, then progress to a total of 45-50 minutes a day, if they could tolerate, by the end of six weeks. Every participant was given a pedometer and a polar heart rate monitor to track step counts and walking heart rate. Both groups returned once a week for discussions about their progress and readjustment of the IMT training intensity based on the new PImax measured..
Measure Participants	3	5
six-minute walk distance at week 1	356.16	378.04
Six-minute walk distance at week 6	375.78	419.71

Adverse Events

Time Frame	Six weeks
Arm/Group Title	Low-intensity IMT Plus Walking		High-intensity IMT Plus Walking
Arm/Group Description	Inspiratory Muscle Training (IMT) intensity is set at 15% PImax. The walking program will consist of walking every day at an intensity of "hard" to "somewhat hard" on the Rating of Perceived Exertion (RPE) scale. Participants will be instructed to walk at 15 minutes twice a day initially, then progress to 45-50 minutes a day by the end of the six weeks. Low-intensity IMT plus walking: The IMT training is about 15-20 minutes. Both groups will need to come in once a week for 15 to 20 minutes to probably readjust the IMT training intensity on the breathing device. For the walking program, each participant will be given a pedometer and a heart rate monitor so he/she can track daily step counts and walking heart rate during the study. The walking program will consist of walking every day at an intensity of "hard" to "somewhat hard" on the Rating of Perceived Exertion (RPE) scale. Participants will begin walking at least 15 minutes twice a day for 7 days a week and eventually pr		Inspiratory Muscle Training (IMT) intensity is set at 60% PImax. The walking program will consist of walking every day at an intensity of "hard" to "somewhat hard" on the Rating of Perceived Exertion (RPE) scale. Participants will be instructed to walk 15 minutes twice a day initially, then progress to 45-50 minutes a day by the end of six weeks. High-intensity IMT plus walking: The IMT intensity will be set at 60% of PImax which will be adjusted weekly and nose clip will be used. Frequency: 5x/week; 1x/day preferred. 6 Interval Levels: (6 efforts at each level): (1) 60s rest interval; (2) 45s rest interval; (3) 30s rest interval; (4) 15s rest interval; (5)10s rest interval; (6) 5s rest interval, trained to exhaustion. For the walking program, each participant will be given a pedometer and a heart rate monitor so he/she can track daily step counts and heart rate during the study. The walking program will consist of walking every day at an intensity of "hard" to "somewhat har
All Cause Mortality
	Low-intensity IMT Plus Walking		High-intensity IMT Plus Walking
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	0/9 (0%)		0/7 (0%)
Serious Adverse Events
	Low-intensity IMT Plus Walking		High-intensity IMT Plus Walking
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	2/9 (22.2%)		1/7 (14.3%)
Cardiac disorders
hospitalization	0/9 (0%)	0	1/7 (14.3%)	1
Respiratory, thoracic and mediastinal disorders
hospitalization	2/9 (22.2%)	2	0/7 (0%)	0
Other (Not Including Serious) Adverse Events
	Low-intensity IMT Plus Walking		High-intensity IMT Plus Walking
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	6/9 (66.7%)		2/7 (28.6%)
Cardiac disorders
transportation issue, relocation, loss to follow up	6/9 (66.7%)	6	2/7 (28.6%)	2

Limitations/Caveats

[Not Specified]

More Information

Certain Agreements

All Principal Investigators ARE employed by the organization sponsoring the study.

There is NOT an agreement between Principal Investigators and the Sponsor (or its agents) that restricts the PI's rights to discuss or publish trial results after the trial is completed.