Research

Hormonal

Non-REM (NREM) sleep is characterized by increased parasympathetic modulation and higher cardiovascular complexity compared to REM sleep, serving as a restorative phase.

Prioritize deep, uninterrupted NREM sleep for cardiovascular recovery. This phase is associated with lower heart rate, blood pressure, and higher autonomic complexity, which are beneficial for long-term heart health.

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transition from wake to NREM sleep is associated with a gradual increase in parasympathetic modulation... NREM sleep is characterized by an increased Sample Entropy
Eleonora Tobaldini et al. · Frontiers in Physiology · 2013

Why this rating

Based on multiple studies cited regarding HRV during NREM sleep.

Source

Heart rate variability in normal and pathological sleep

Eleonora Tobaldini et al. · Frontiers in Physiology · 2013

DOI 10.3389/fphys.2013.00294

narrative_reviewCited 371×
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DOI resolved against Crossref · corpus check 2026-06-10

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