Yoga breathing exercise linked to lower stress and better sleep in women undergoing chemotherapy

Perceived stress was measured using the Perceived Stress Scale and sleep quality using the Pittsburgh Sleep Quality Index at baseline and after 21 days. The yoga breathing group showed a mean reduction in perceived stress of 6.23 points (p < 0.001) and improved sleep quality by 2.1 points (p < 0.001) compared with the sham group. No adverse events were reported in either group. The study design—a sham-controlled randomized trial—strengthens confidence in the findings, though the 21-day timeframe and hospital-based population limit how long effects persist and how well results generalize to all women with cancer. The authors conclude that yoga breathing exercise may complement standard supportive oncology care as a low-cost, accessible intervention for chemotherapy-related stress and sleep disturbance.

The effect sizes are clinically meaningful: a 6-point reduction on the Perceived Stress Scale represents a shift from moderate to mild stress, and the 2.1-point improvement on the Pittsburgh Sleep Quality Index suggests movement from poor toward fair sleep. The 4-4-4-4 pattern (often called box breathing) activates the parasympathetic nervous system, the body's rest-and-recover branch, which is commonly dysregulated during cancer treatment and chemotherapy-induced anxiety. Subgroup analysis was not reported, so it remains unclear whether the effect differed by age, chemotherapy regimen, or baseline stress level. The short intervention window (21 days, twice daily) makes this practical for integration into hospital routines, though longer follow-up would clarify whether benefits persist after chemotherapy ends. No safety signals emerged, which is important because cancer patients often worry about adding anything to their treatment plan.