Effects of a 4-week Vinyasa Yoga Intervention on Sleep and Cardiovascular Health in Adults with Insomnia Symptoms: A Pilot Randomized Controlled Trial

Abstract

Vinyasa yoga (VY) yields moderate-intensity physical activity that may improve sleep and cardiovascular health (CVH). However, evidence is scarce regarding the effects of VY on CVH. This study examined the effects of a 4-week VY intervention on sleep and CVH in adults with insomnia symptoms. 33 insufficiently active adults (84.8% female; 78.8% White; 34.9±10.6 y; 28.9 kg/m2) with insomnia symptoms (Insomnia Severity Index [ISI]≥10) were randomized to a 4-week VY intervention (n=17) or non-active control (CON; n=16). VY participants practiced 3x/week following pre-recorded 60-minute videos and CON maintained their current lifestyle. Resting daytime blood pressure (BP), heart rate (HR), and HR variability (HRV) were obtained at baseline and post-intervention. Sleep was measured using the ISI, actigraphy, and a sleep diary. One night during sleep assessment, participants wore a chest HR monitor to assess HRV; primary HRV outcome was root mean square of successive differences. Analyses used linear mixed models and Cohen’s d effect sizes. Changes in ISI, actigraphy- and diary-assessed sleep from baseline to post-intervention did not differ between groups (each p>0.06). Changes in nocturnal HRV and daytime resting BP and HRV were not significant (each p≥0.30). Resting HR decreased for VY (72.41±2.92 to 69.50±2.60 bpm) and increased for CON (70.47±2.54 to 72.93±2.60 bpm) (p=0.047). Additionally, among highly adherent participants, VY reduced ISI scores more than CON (p=0.002). VY improves insomnia symptoms among those who practice regularly. It does not appear to improve nocturnal cardiovascular physiology, and shows modest benefits on daytime cardiac parasympathetic activity. Registry: ClinicalTrials.gov; Name: Yoga for Insomnia (YOGi) Study; URL: https://clinicaltrials.gov/study/NCT05723211; Registration ID: NCT0572321; Date of Registration: 2/01/2023