Comparing Nose & Mouth Breathing During Exercise

Study Overview
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Brief Summary
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The purpose of this study is to compare physiological responses in cardiovascular variables between nose and mouth breathing at rest and during exercise.

Detailed Description
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Breathing patterns can affect the cardiovascular system. Little is known about how nose versus mouth breathing affects cardiovascular variables (blood pressure, heart rate, etc.) at rest and during exercise. It has been suggested that breathing through the nose can cause calmness and lower blood pressure. However, research is needed to examine the extent to which breathing through the nose affects cardiovascular variables at rest and during exercise. Therefore, we will compare cardiovascular variables between nose-only and mouth-only breathing. The rate of breathing will be fixed (using an audible metronome) for both breathing conditions (nose-only vs mouth-only) based on an individual's free breathing (i.e., no breathing cues) breathing rate.

Official Title
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Comparing Nose & Mouth Breathing During Exercise

Conditions
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Healthy

Intervention / Treatment
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* Behavioral: Nose-only breathing
* Behavioral: Mouth-only breathing


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Body mass index: ≤30 kg/m2 Resting Blood pressure: ≤140/90 mmHg Exclusion Criteria: Overt cardiovascular (e.g., diagnosed hypertension), respiratory, neurological, renal, liver, and/or metabolic health condition Current or recent (regular use within the past 6 months) use of tobacco or nicotine products (e.g., cigarettes)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 30 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: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Nose-only breathing<br>Participants will be instructed to breathe only through their nose (mouth closed) during rest and submaximal exercise. | Behavioral: Nose-only breathing<br>* Participants will breathe only through their nose (mouth closed) during rest and submaximal exercise.<br>|
| Active Comparator: Mouth-only breathing<br>Participants will be instructed to breathe only through their mouth (nose clips prevent nose breathing) during rest and submaximal exercise. | Behavioral: Mouth-only breathing<br>* Participants will breathe only through their mouth (nose clips prevent nose breathing) during rest and submaximal exercise.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Blood pressure during exercise between study arms | Systolic and diastolic blood pressure will be measured in the laboratory at rest and during submaximal exercise with nose-only breathing and mouth-only breathing. | Up to one day | 
| Heart rate during exercise between study arms | Heart rate will be measured in the laboratory at rest and during submaximal exercise with nose-only breathing and mouth-only breathing. | Up to one day | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rating of perceived exertion during exercise between study arms | Participants will report their rating of perceived exertion (numerical scores of 6-20, with 20 being the greatest exertion) based on a validated scale at rest and during submaximal exercise with nose-only breathing and mouth-only breathing. | Up to one day | 
| Rating of perceived breathlessness during exercise between study arms | Participants will report their rating of perceived breathlessness (numerical scores of 0-10, with 10 being the greatest breathlessness) based on a validated scale at rest and during submaximal exercise with nose-only breathing and mouth-only breathing. | Up to one day |