Different breathwork practices –
https://therenegadepharmacist.com/breathwork-breathwork-demystified-science-purpose-different-breathwork-practices/

Heart Rate Variability (HRV) –
https://therenegadepharmacist.com/heart-rate-variability/

The Effects of Intermittent Hypoxia on Stem Cell Differentiation –
https://therenegadepharmacist.com/hypoxia-stem-cell-differentiation/

The Benefits of Intermittent Hypoxic training –

https://therenegadepharmacist.com/intermittent-hypoxic-training/

Nisshesha rechaka pranayama offers benefits through brief intermittent hypoxia:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3361916/

Therapeutic potential of intermittent hypoxia: a matter of dose
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4315448/

Therapeutic benefits of AUM
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3099099/

Great article on the movement of Cerebral Spinal Fluid during breathing
http://www.anthromed.org/Article.aspx?artpk=393

 How humming on the out breath increases the production of Nitric Oxide 15 fold

https://erj.ersjournals.com/content/22/2/323