Not that I have searched too much but I haven't seen a weightlifting, gym club. I'm not sure how much traction it would get but I would start one of enough people seem interested. It has been my main hobby, interest ,besides cooking, since probably high school when we lifted for wrestling and football. It wouldn't have to be strictly for lifting but it could be any kind of excercising but I would prefer just lifting since there is already a lot you can cover on the topic.
As much as I adore scifi, maybe it's a bit too broad? Considering how many things and fandoms can fit under it.
Club idea, what if we had a sci-fi lovers club? There you could discuss your favorite science-fiction movies, animes and books, we could even read novels tgether as a clubhouse activity, share ideas for your own-sci fi stories, world-building exercises, watch science documentaries, moon landing footage, and share real news events of cutting edge technology, inventions and scientifc breakthroughs and discoveries. This club would be dystopian societies, robotics and androids, time and space travel and alternate dimensions, extraterrestrials and more.