Effects of Respiratory Yoga Training on Heart Rate Variability and Baroreflex of Healthy Elderly Subjects

Study Overview
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Brief Summary
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The decreases of physiological capacities which take place with senescence include diminishing respiratory capacity as well as a reduction of heart rate variability and baroreflex sensibility. Altogether, these alterations increase elderly people's frailty and have a negative impact over quality of life. Since Yoga (Indian auto-discipline) has a wide range of respiratory exercises already investigated as components for non-pharmacological treatments for hypertension (situation in which heart rate variability is also diminished), the investigators hypothesis is that the training of respiratory exercises of Yoga may have a significant positive effect on heart rate variability and baroreflex of health elderly subjects, increasing quality of life and reducing frailty. We included 30 health elderly subjects (both sexes, from 60 years-old onwards) divided into 2 randomized experimental groups: control (C) and respiration (R). Each group underwent an entry evaluation, followed by a 4-months training period, after which they were re-evaluated. Control consisted of 2 stretching classes per week, and respiration consisted of 2 respiratory exercises classes a week. Both groups were instructed to perform the exercises at home twice a day, and to keep a record of each session in a log sheet. Evaluations were: WHOQOL-OLD questionnaire for quality of life, 20 minutes of seated rest with heart rate, respiration and blood pressure acquired continuously for further spectral analysis.

Detailed Description
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Heart rate variability was performed using the autoregressive model, and the baroreflex was calculated with the spontaneous approach, both with the softwares developed in Milan by Alberto Porta in a non-invasive way. The frequency domain analysis of heart rate, respiration and systolic blood pressure were conducted, consisting of calculating the power spectral density with the minimum error predicted by Akaike's algorithm. Spectral power was then subdivided into two bands of physiological interest: low - (LF 0.03-0.15 Hz) indicating predominant sympathetic modulation, and high - (HF 0.15-0.5 Hz) frequency, indicating parasympathetic modulation of the heart. The fraction calculated dividing LF by HF (LF/HF ratio) provided information of sympathovagal balance to the heart. The spectral analysis of Systolic Blood Pressure provided information of the vasomotor tone, and the integration of heart rate information with these data also provided information about the spontaneous baroreflex gain. Other questionnaires used were: Pittsburgh Quality of Sleep Questionnaire, Stress Symptoms Questionnaire by Marilda Lipp - validated in Brazil, and Beck's anxiety and depression inventories.

Official Title
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Effects of Respiratory Yoga Training (Bhastrika) on Heart Rate Variability and Baroreflex, and Quality of Life of Healthy Elderly Subjects

Conditions
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Elderly Subjects, Respiration Exercises

Intervention / Treatment
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* Other: Stretching Exercises
* Other: Respiratory Exercises conducted twice a day for 10 minutes


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Health elderly subjects Exclusion Criteria: Use of beta-blockers Atrial Fibrillation Previous training in respiratory exercises

Ages Eligible for Study
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Minimum Age: 60 Years
Maximum Age: 85 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Sham Comparator: Control Group<br>Stretching exercises performed twice a day for 10 minutes (4 months) | Other: Stretching Exercises<br>* Conducted twice a week, with instructions for home exercises twice a day, and registering each session on a log sheet.<br>|
| Active Comparator: Respiration Group<br>Respiratory Yoga exercises performed twice a day for 10 minutes (4 months) | Other: Respiratory Exercises conducted twice a day for 10 minutes<br>* Conducted twice a week, with instructions for home exercises twice a day, and registering each session on a log sheet.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Heart Rate Variability |  | 4 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| baroreflex gain |  | 4 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Healthy Elderly Subjects, Respiratory Yoga Exercises, Heart Rate Variability, Baroreflex, Quality of Life