I think the important thing is only that you exhale longer than you inhale. Inhaling activates SNS, exhaling PNS, the latter is for relaxation. So the more you

I think the important thing is only that you exhale longer than you inhale. Inhaling activates SNS, exhaling PNS, the latter is for relaxation. So the more you can tilt that ratio towards exhaling while still breathing comfortably the better