Yoga-Based Breathing Exercises in a Salt-Cave Environment Versus a Standard Clinical Setting in Smokers (SPELEO-SMOKERS)
July 27, 2026 updated by: SEFA HAKTAN HATIK, Sinop University
Yoga-Based Breathing Exercises Performed in a Salt-Cave Environment Versus a Standard Clinical Setting in Smokers: A Randomized Controlled Trial
This randomized controlled trial evaluated whether performing the same yoga-based breathing exercise program in a salt-cave environment produced different respiratory, functional, physical activity, and quality-of-life outcomes compared with the same program performed in a standard clinical setting in adult smokers.
Sixty adult smokers were randomized to either a salt-cave group or a control group.
Both groups received a physiotherapist-supervised yoga-based breathing exercise program for 6 weeks, twice weekly, in 50-minute sessions.
The intervention content, frequency, duration, and physiotherapist supervision were identical in both groups; the only planned between-group difference was the intervention setting.
Spirometric outcomes were assessed at baseline, week 3, and week 6.
Functional exercise capacity, physical activity, and quality of life were assessed at baseline and week 6.
Study Overview
Status
Completed
Conditions
Detailed Description
Eligible participants were adult daily smokers aged 18 to 65 years who had smoked for at least the previous 12 months.
After baseline assessments, participants were randomized in a 1:1 ratio to the salt-cave group or the standard clinical setting group.
Allocation was generated by an independent researcher and concealed using sequentially numbered, opaque, sealed envelopes.
Both groups completed the same 6-week yoga-based breathing exercise program, delivered twice weekly under physiotherapist supervision.
Each standardized session lasted approximately 50 minutes and included preparatory breathing control, diaphragmatic breathing, Suusi breathing, Kapalabhati, Ujjayi, Anuloma-Viloma/Nadi Shodhana, Bhastrika, Bhramari, Agni Sar, and relaxation.
The salt-cave group received the program at the Tuzluca Salt Therapy Center, whereas the control group received the program in a standard private clinical setting.
Spirometric parameters included forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), peak expiratory flow (PEF), and the FEV1/FVC ratio.
Secondary assessments included the 6-minute walk test, the International Physical Activity Questionnaire-Short Form, and the World Health Organization Quality of Life-BREF.
Participant and provider blinding was not feasible because the settings were visibly different.
Statistical analysis was conducted using coded group labels.
Study Type
Interventional
Enrollment (Actual)
60
Phase
- Not Applicable
Contacts and Locations
This section provides the contact details for those conducting the study, and information on where this study is being conducted.
Study Locations
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-
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Iğdır, Turkey (Türkiye), 76900
- Tuzluca Rock Salt Mine Salt Therapy Center
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-
Participation Criteria
Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.
Eligibility Criteria
Ages Eligible for Study
- Adult
- Older Adult
Accepts Healthy Volunteers
Yes
Description
Inclusion Criteria:
- Adults aged 18 to 65 years
- Voluntary participation and written informed consent
- Ability to ambulate and cooperate with assessments
- Literacy
- Daily smoking for at least the previous 12 months
- Body mass index below 30 kg/m²
Exclusion Criteria:
- Adults aged 18 to 65 years
- Voluntary participation and written informed consent
- Ability to ambulate and cooperate with assessments
- Literacy
- Daily smoking for at least the previous 12 months
- Body mass index below 30 kg/m²
Withdrawal Criteria
- Participant request to discontinue
- Pregnancy or suspected pregnancy
- Occurrence of a sports-related injury during assessments
Study Plan
This section provides details of the study plan, including how the study is designed and what the study is measuring.
How is the study designed?
Design Details
- Primary Purpose: Treatment
- Allocation: Randomized
- Interventional Model: Parallel Assignment
- Masking: None (Open Label)
Arms and Interventions
Participant Group / Arm |
Intervention / Treatment |
|---|---|
|
Experimental: Salt-Cave Yoga-Based Breathing Exercise Group
Participants completed the physiotherapist-supervised yoga-based breathing exercise program at the Tuzluca Salt Therapy Center for 6 weeks, twice weekly.
The program content, session duration, frequency, and supervision were identical to those of the comparator group; the planned between-group difference was the intervention setting.
|
Participants received a physiotherapist-supervised yoga-based breathing exercise program at the Tuzluca Salt Therapy Center.
The intervention lasted 6 weeks and included two sessions per week, for a total of 12 sessions.
Each standardized session lasted approximately 50 minutes and included preparatory breathing control, diaphragmatic breathing, Suusi breathing, Kapalabhati, Ujjayi, Anuloma-Viloma/Nadi Shodhana, Bhastrika, Bhramari, Agni Sar, and relaxation.
The exercise content, session frequency, duration, and physiotherapist supervision were identical to those provided in the standard clinical setting group; the planned difference was the intervention setting.
|
|
Active Comparator: Standard Clinical Setting Yoga-Based Breathing Exercise Group
Participants completed the same physiotherapist-supervised yoga-based breathing exercise program at the Iğdır Fizyodinamik Wellness Center for 6 weeks, twice weekly.
The program content, session duration, frequency, and supervision were identical to those of the experimental group.
|
Participants received the same physiotherapist-supervised yoga-based breathing exercise program in a standard clinical setting at the Iğdır Fizyodinamik Wellness Center.
The intervention lasted 6 weeks and included two sessions per week, for a total of 12 sessions.
Each standardized session lasted approximately 50 minutes and included preparatory breathing control, diaphragmatic breathing, Suusi breathing, Kapalabhati, Ujjayi, Anuloma-Viloma/Nadi Shodhana, Bhastrika, Bhramari, Agni Sar, and relaxation.
The exercise content, session frequency, duration, and physiotherapist supervision were identical to those provided in the salt-cave group.
|
What is the study measuring?
Primary Outcome Measures
Outcome Measure |
Measure Description |
Time Frame |
|---|---|---|
|
Change in Forced Expiratory Volume in 1 Second (FEV1) From Baseline to Week 6
Time Frame: Baseline, week 3, and week 6; primary endpoint at week 6
|
FEV1 was measured in liters using pre-bronchodilator spirometry.
Participants performed three forced expiratory maneuvers under standardized instruction, and the best acceptable value was recorded.
The primary comparison was the between-group difference in change from baseline to week 6.
An interim measurement was also obtained at week 3
|
Baseline, week 3, and week 6; primary endpoint at week 6
|
Secondary Outcome Measures
Outcome Measure |
Measure Description |
Time Frame |
|---|---|---|
|
Change in Forced Vital Capacity (FVC) From Baseline to Week 6
Time Frame: Baseline, week 3, and week 6
|
FVC in liters, measured by pre-bronchodilator spirometry; baseline, week 3, and week 6.
|
Baseline, week 3, and week 6
|
|
Change in Peak Expiratory Flow (PEF) From Baseline to Week 6
Time Frame: Baseline, week 3, and week 6
|
PEF in L/s, measured by pre-bronchodilator spirometry; baseline, week 3, and week 6.
|
Baseline, week 3, and week 6
|
|
Change in FEV1/FVC Ratio From Baseline to Week 6
Time Frame: Baseline, week 3, and week 6
|
FEV1/FVC expressed as a percentage; baseline, week 3, and week 6.
|
Baseline, week 3, and week 6
|
|
Change in 6-Minute Walk Distance From Baseline to Week 6
Time Frame: Baseline and week 6
|
Distance walked in meters during the 6-minute walk test.
Two tests were administered and the longest distance was used; baseline and week 6.
|
Baseline and week 6
|
|
Change in Physical Activity Assessed by IPAQ-SF From Baseline to Week 6
Time Frame: Baseline and week 6
|
Total physical activity expressed as MET-min/week using the standard IPAQ-SF scoring protocol; baseline and week 6.
|
Baseline and week 6
|
|
Change in WHOQOL-BREF Scores From Baseline to Week 6
Time Frame: Baseline and week 6
|
Changes in General Health, Physical Health, Psychological, Social Relationships, and Environment scores; baseline and week 6.
|
Baseline and week 6
|
|
Participants With Intervention-Related Adverse Events
Time Frame: 6-week study period
|
Number of participants experiencing intervention-related or spirometry-related adverse events during the 6-week study period.
|
6-week study period
|
Collaborators and Investigators
This is where you will find people and organizations involved with this study.
Sponsor
Publications and helpful links
The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.
General Publications
- Kaminsky DA, Guntupalli KK, Lippmann J, Burns SM, Brock MA, Skelly J, DeSarno M, Pecott-Grimm H, Mohsin A, LaRock-McMahon C, Warren P, Whitney MC, Hanania NA. Effect of Yoga Breathing (Pranayama) on Exercise Tolerance in Patients with Chronic Obstructive Pulmonary Disease: A Randomized, Controlled Trial. J Altern Complement Med. 2017 Sep;23(9):696-704. doi: 10.1089/acm.2017.0102. Epub 2017 Jul 17.
- Dinesh T, Gaur G, Sharma V, Madanmohan T, Harichandra Kumar K, Bhavanani A. Comparative effect of 12 weeks of slow and fast pranayama training on pulmonary function in young, healthy volunteers: A randomized controlled trial. Int J Yoga. 2015 Jan;8(1):22-6. doi: 10.4103/0973-6131.146051.
- Rashleigh R, Smith SM, Roberts NJ. A review of halotherapy for chronic obstructive pulmonary disease. Int J Chron Obstruct Pulmon Dis. 2014 Feb 21;9:239-46. doi: 10.2147/COPD.S57511. eCollection 2014.
- Freidl J, Huber D, Braunschmid H, Romodow C, Pichler C, Weisbock-Erdheim R, Mayr M, Hartl A. Winter Exercise and Speleotherapy for Allergy and Asthma: A Randomized Controlled Clinical Trial. J Clin Med. 2020 Oct 15;9(10):3311. doi: 10.3390/jcm9103311.
Study record dates
These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.
Study Major Dates
Study Start (Actual)
December 1, 2022
Primary Completion (Actual)
February 20, 2023
Study Completion (Actual)
February 28, 2023
Study Registration Dates
First Submitted
July 27, 2026
First Submitted That Met QC Criteria
July 27, 2026
First Posted (Actual)
July 30, 2026
Study Record Updates
Last Update Posted (Actual)
July 30, 2026
Last Update Submitted That Met QC Criteria
July 27, 2026
Last Verified
July 1, 2026
More Information
Terms related to this study
Keywords
Additional Relevant MeSH Terms
Other Study ID Numbers
- SPELEO-SMOKERS-2022
Plan for Individual participant data (IPD)
Plan to Share Individual Participant Data (IPD)?
NO
IPD Plan Description
Individual participant data will not be shared with external researchers.
Drug and device information, study documents
Studies a U.S. FDA-regulated drug product
No
Studies a U.S. FDA-regulated device product
No
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