Exercise to Strengthen the LES

This is the first time I have heard that an exercise exists that strengthens the LES muscle (which is involuntary).

https://www.ncbi.nlm.nih.gov/pmc/articles/pmc9106553/

In his anecdotal report, the author claims to have completely cured (moderate-severity) GERD just by performing this exercise daily for 2+ months. He has not experienced a relapse for 2 years after the initial relief.

There are a lot of claims on the internet, not all of them are legitimate.

Sharon