So there's the first stage of what we call nadishudi pranayam which is alternate nostril breathing but then there's a text called um vashishta samita which talks about a particular kind of cardiac coherence breathing with a a ratio of 1:4 to 8. So you breathe in for 8 seconds. Actually you breathe in for 16 seconds you hold for 64 seconds and then you exhale for 32 seconds.