Acute Effects of Two Slow-Paced Breathing Protocols With and Without Inspiratory Breath-Holding on Heart Rate Variability: A Randomized Controlled Trial

Background/Objectives: Slow-paced breathing (SPB) is associated with changes in heart rate variability, although these responses are strongly influenced by respiratory patterns; the effects of incorporating an inspiratory breath-hold into an SPB protocol remain insufficiently characterized. This study evaluated the immediate effects of two SPB protocols on heart rate variability (HRV) and cervical pressure pain thresholds (PPT).