https://www.tellmeinspanish.com/vocab/gym-and-workout-vocabulary-in-spanish/ Here is good list to start with for general gym going vocabulary. The phrases you’re citing are used in English slang, so it’s not likely that there is a 1:1 equivalent. More on reddit.com

I was in a secondary school and had a lot of PE classes. Overall I think it's a waste of our time but I didn't complain because it was fresh air and I didn't really do much. Whenever a class learned a new sport (maybe once a month?) I would do a presentation on the sport (rules, ect) in English. But mostly I would just stand around. I also am not super athletic, so mostly I would watch the kids play sports/ and supervise. Occasionally I would jump in a casual game or soccer passing exercise. One professor of 4° ESO realized that there's not much for me to do, so he would have me talk to the kids in groups about random topics of my choice or maybe related to the sport/lesson, just to get them speaking English. More on reddit.com

Yes. More on reddit.com

From C1 speaker studying abroad in Spain who just started going to the gym: Dumbbell: typically just pesa, even though that can also refer to any weight. I believe mancuerna is more specific to dumbbell but I haven’t personally heard someone say it. They are marketed as mancuerna at decathalon Set: serie, or sometimes the English loanword “set” Rep: repetición, sometimes “rep” Drop set: it seems it’s just drop set. I haven’t heard this term but googling it shows multiple Spanish language blogs using the loan word as a feminine noun. Super set: superserie or super set Push ups: lagartijas or push-ups Bench press: press de banca or press de pecho Squat: sentadilla Chest fly: apertura de pecho or fly de pecho Leg press: prensa de pierna or press de pierna Generally, the more technical or advanced the bodybuilding vocabulary is, the more likely it will be an English calque or loanword, often with only the body part translated. The gym I go to doesn’t even bother to localize the names of the exercises printed on the machines; they are all written in English. More on reddit.com