Four-week Breathing Interventions on Gut Symptoms, Heart Rate Variability, and Psychological Measures in Runners

Study Overview
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Brief Summary
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Recent research has suggested that stress and anxiety levels are associated with gastrointestinal (GI) symptoms in endurance athletes (runners, cyclists, triathletes). Yet, there has been limited attempt to evaluate whether GI symptoms during running can be mitigated by interventions designed to reduce stress and anxiety. Thus, this study will evaluate the effects of four-week slow deep breathing and mindful breath counting interventions on subjective and objective measures of stress/anxiety and GI symptoms in runners with mild-to-high anxiety and that are prone to GI symptoms during runs.

Official Title
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The Effects of Four-week Breathing Interventions on Gastrointestinal Symptoms, Heart Rate Variability, and Psychological Measures in Runners

Conditions
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Gastrointestinal System--Abnormalities, Anxiety, Visceral Pain

Intervention / Treatment
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* Behavioral: Slow deep breathing plus breath counting
* Behavioral: Normal-paced breathing plus breath counting


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: At least 18 years of age Run at least 15 miles per week Access to internet Access to a smart phone that is compatible with iOS or Android applications Score at least a 5 on the GAD-7 Report to have experienced GI symptoms sometimes, often or always during runs in the previous month. If on a psychotropic medication, must be on a stable dose for the past 3 months. Live within the contiguous United States Exclusion Criteria: Younger than 18 years Run less than 15 miles per week Do not have access to the internet Do not have access to a smart phone that is compatible with iOS or Android applications Score less than 5 on the GAD-7 Report to have never or rarely experienced GI symptoms during runs in the previous month Are being prescribed a psychotropic medication and have not had a stable dose for at least three months. Do not live within the contiguous United States

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Slow deep breathing plus breath counting<br>Participants in this group will do a daily 5-min slow deep breathing exercise (6 breaths/minute) and will also count their breaths | Behavioral: Slow deep breathing plus breath counting<br>* Participants will perform a daily 5-min slow deep breathing exercise for 4 weeks. A breathing rate of 6 breaths per minute will be targeted. In addition, participants will count their breaths during the exercise.<br>|
| Active Comparator: Normal-paced breathing plus breath counting<br>Participants in this group will do a daily 5-min normal-paced breathing (15 breaths/minute) and will also count their breaths | Behavioral: Normal-paced breathing plus breath counting<br>* Participants will perform a daily 5-min normal-paced breathing exercise for 4 weeks. A breathing rate of 15 breaths per minute will be targeted. In addition, participants will count their breaths during the exercise.<br>|
| No Intervention: Control<br>Participants in this group will serve as a control and will not do any breathing exercises or breath counting. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in gastrointestinal symptom occurrence | Percentage of training runs that runners experience at least 1 gastrointestinal symptom (>2 on 0-10 scale). | The intervention will last 4 weeks. Gastrointestinal symptoms will be collected for a 1-week period before the intervention and during the 4th week of the intervention. | 
| Change in anxiety levels | Levels of anxiety will be assessed with the General Anxiety Disorder-7 questionnaire. Scores on the General Anxiety Disorder-7 range from 0 to 21, with higher scores indicating higher levels of anxiety. | The intervention will last 4 weeks. The General Anxiety Disorder-7 will be assessed before the intervention begins, 2 weeks into the intervention, and at the end of the intervention. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in visceral sensitivity | Perceptions of visceral sensitivity will be assessed via the Visceral Sensitivity Index. Scores on the Visceral Sensitivity Index can range from 0 to 75, with higher scores indicating a higher level of visceral sensitivity. | The intervention will last 4 weeks. The Visceral Sensitivity Index will be assessed before the intervention begins, 2 weeks into the intervention, and at the end of the intervention. | 
| Change in mindfulness | Perceptions of mindfulness will be assessed via the 15-item Five Facet Mindfulness Questionnaire. Scores on the Five Facet Mindfulness Questionnaire can range from 15-75, with higher scores indicating higher levels of mindfulness. | The intervention will last 4 weeks. The Five Facet Mindfulness Questionnaire will be assessed before the intervention begins, 2 weeks into the intervention, and at the end of the intervention. | 
| Change in body vigilance | Perceptions of body vigilance will be assessed via the Body Vigilance Scale. Scores on the Body Vigilance Scale can range from 0-40, with higher levels meaning greater amounts of body vigilance. | The intervention will last 4 weeks. The Body Vigilance Scale will be assessed before the intervention begins, 2 weeks into the intervention, and at the end of the intervention. | 
| Change in heart rate variability (Ln RMSSD) | Heart rate variability will be assessed via a portable fingertip monitor (CorSense) and quantified as the Ln root mean square of successive differences (Ln RMSSD) between normal heartbeats. | The intervention will last 4 weeks. Ln RMSSD will be assessed before the intervention begins, and at the end of the intervention. |