https://briannox.com/ for more tips and in-depth videos.
Getting my book for free on audible when you start a trial?
https://briannox.com/audible/

https://amzn.to/2Fnf2xD to find all my books on Amazon.com
(This is an Amazon Affiliate Link. As an Amazon Associate, I earn from qualifying purchases.)

Some interesting studies:
https://www.bbc.com/news/science-envi...
https://www.ncbi.nlm.nih.gov/pmc/arti...
https://pubmed.ncbi.nlm.nih.gov/10941...
https://www.sciencedirect.com/science...
https://stanmed.stanford.edu/how-mens...