That's the bro-science conclusion of what causes a distended abdomen. Here's a list of what medical science says can cause distended abdomen:
https://en.wikipedia.org/wiki/Abdominal_distension
Note there are about two dozen things that can cause it. Now ask yourself, do you trust bro-science or medical science? For instance, if you were in a bad car accident, would you want the ambulance to take you to a hospital for medical science treatment, or to a gym locker for bro-science treatment?
Me, I'd go with the hospital every time, so I believe medical science over bro-science.