Relaxation Effects of Personalized Breathing Exercises for Healthy College Students

Study Overview
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Brief Summary
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Stress plays a major role in the etiology and pathogenesis of anxiety and depression. Relaxation therapies, such as breathing exercises, can reduce stress and increase relaxation. This study has two aims. First, it aims to personalize and optimize breathing protocols. Second, it aims to tailor breathing protocols to subgroups based on prediction models of expected efficacy. Three different breathing protocols, varying solely in their instructed breathing frequency with 40 percent (A), 60 percent (B), and 80 percent (C) of the interindividual spontaneous breathing frequency, are tested in a randomized, counterbalanced crossover trial. Other parameters, such as breathing quality (i.e., nasal and diaphragmatic), rhythm (i.e., prolonged exhalation without instructed pauses) and depth (i.e., increased depth due to slower breathing frequency) as well as contextual factors (e.g., posture, video-based instructions, type of pacer, etc.) are invariant between protocols. First, this study hypothesizes a difference in the relaxation response between breathing protocols A, B, and C. This study looks at the relaxation response from three different angles (1) self-report, (2) autonomic arousal, and (3) central nervous system arousal. Second, this study explores prediction models of expected efficacy based on the interindividual variance in characteristics (i.e., depressive, anxious and stress symptoms as well as expertise in relaxation therapies) and biomarkers (e.g., heart rate variability, peripheral temperature, skin conductance, etc.). Prediction models can tailor breathing protocols to subgroups to increase expected efficacy.

Official Title
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Relaxation Effects of Personalized Breathing Exercises for Healthy College Students: A Randomized Crossover Trial

Conditions
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Breathing Exercises

Intervention / Treatment
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* Behavioral: Breathing Exercise


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Above 18 years old University student Native German speaker Exclusion Criteria: Any psychiatric (e.g., anxiety), neurologic (e.g., epilepsy) or cardio-pulmonary (e.g., asthma) diagnosis

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: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Breathing Exercise with 40 Percent of the Spontaneous Breathing Frequency (A)<br>Participants are instructed (via visual pacer) to reduce their breathing frequency to 40 percent of their spontaneous breathing frequency for a period of five minutes. In advance, participants are instructed (via pre-recorded video) to breathe nasally (if possible) and abdominally, with a prolonged exhalation (inspiration-to-expiration ratio is 1-to-2 - also instructed via visual pacer) during the breathing exercise. | Behavioral: Breathing Exercise<br>* A breathing exercise is a relaxation technique (or therapy) to increase relaxation (induces a relaxation response) and decrease stress (reduces a stress response).<br>|
| Experimental: Breathing Exercise with 60 Percent of the Spontaneous Breathing Frequency (B)<br>Participants are instructed (via visual pacer) to reduce their breathing frequency to 60 percent of their spontaneous breathing frequency for a period of five minutes. In advance, participants are instructed (via pre-recorded video) to breathe nasally (if possible) and abdominally, with a prolonged exhalation (inspiration-to-expiration ratio is 1-to-2 - also instructed via visual pacer) during the breathing exercise. | Behavioral: Breathing Exercise<br>* A breathing exercise is a relaxation technique (or therapy) to increase relaxation (induces a relaxation response) and decrease stress (reduces a stress response).<br>|
| Experimental: Breathing Exercise with 80 Percent of the Spontaneous Breathing Frequency (C)<br>Participants are instructed (via visual pacer) to reduce their breathing frequency to 80 percent of their spontaneous breathing frequency for a period of five minutes. In advance, participants are instructed (via pre-recorded video) to breathe nasally (if possible) and abdominally, with a prolonged exhalation (inspiration-to-expiration ratio is 1-to-2 - also instructed via visual pacer) during the breathing exercise. | Behavioral: Breathing Exercise<br>* A breathing exercise is a relaxation technique (or therapy) to increase relaxation (induces a relaxation response) and decrease stress (reduces a stress response).<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| General Relaxation Score | Measured with the German Version of the Relaxation State Questionnaire | Immediately after the 5-minute baseline measurement and immediately after each 5-minute breathing exercise | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Current Perceived Stress Level | Measured on a visual analog scale ranging from 0 to 100, where zero is absolutely no stress and 100 is extreme stress. | Immediately after the 5-minute baseline measurement and immediately after each 5-minute breathing exercise | 
| Heart Rate Variability | Measured via blood volume pulse with a finger clip on the middle finger | During the 5-minute baseline measurement and during each 5-minute breathing exercise | 
| Peripheral Temperature | Measured via temperature sensor on the small finger | During the 5-minute baseline measurement and during each 5-minute breathing exercise | 
| Skin Conductance | Measured via skin conductance sensor on the index and ring finger | During the 5-minute baseline measurement and during each 5-minute breathing exercise | 
| Power in Frequency Bands | Measured via four channel EEG with linked earlobe reference and active electrode placement on F3, F4, F7, and F8 according to the international 10-20 system | During the 5-minute baseline measurement and during each 5-minute breathing exercise | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Relaxation therapy, Stress-management, Breathing exercise, Anxiety, Depression, Stress