Obsessed with bodybuilding

A friend of mine has recently become interested in bodybuilding. I thought it was fine at first, he gained some weight, looked much stronger and attractive. Sometimes I even went to the gym with him. But unfortunately there is a thin boundary between the willingness to exercise and being obsessed with it. I left the country for three months so we didn"t actually see each other for a long time, and when we finally met I barely recognised him. It"s not that he looked different. True, his muscles had developed a lot and I was really impressed with that at first. But then I noticed another change. There was something wrong with the way he talked. Workout and supplements were his favourite topics and it was actually difficult to make him interested in anything else. Now it"s all different. We"re still friends, but we don"t see each other very often. We used to go jogging together, but now he doesn"t want to hear about it. He says any kind of aerobic exercise can destroy his muscles and the only thing he should focus on is bodybuilding. He has even mentioned something about taking part in bodybuilding competitions. Well, I wish him good luck. But I hope he changes his mind one day. He needs a variety of exercises, as we all do, and what"s the point in being a strongman if you lose your breath every time you want to catch a train?