Magnon · Scientific reports 2021 · non-randomized comparative trial · n=47

Benefits from one session of deep and slow breathing on vagal tone and anxiety in young and older adults.

Level 3 - non-randomized controlled study

Non-randomized comparative cohort trial evaluating pre-post intervention effects across age groups

PubMed 34588511 · doi:10.1038/s41598-021-98736-9 · record verified 2026-08-26

What was done

Researchers tested the acute effects of a single session of deep and slow breathing (DSB, using a low inhale-to-exhale ratio) on physiological stress and anxiety. The study compared 22 older adults with 25 younger adults, measuring heart rate variability metrics (HF power and RMSSD) for vagal tone and self-reported state anxiety.

What was found

The abstract reports no exact numerical values, effect sizes, or p-values. It states that DSB significantly increased HF power and reduced state anxiety in both age cohorts. The increase in HF power was significantly larger in older adults than in younger adults. RMSSD did not increase post-intervention in either group.

Why it matters

Slow-paced breathing exercises can acutely reduce state anxiety across adulthood and may provide a greater relative boost to cardiac vagal modulation in older populations.

Limits

The study evaluated only a single acute session with a small sample size (total n = 47) and lacked a non-breathing control group. The abstract omits exact statistical values, baseline clinical characteristics, and long-term functional or clinical outcomes.