How long should i wait before going back to the gym after an appendix surgery? it was an open surgery, 4.5 cm incision. i'm 25 yo.

A few weeks: Wounds in healthy people reach 70-80% of full healed strength in about a month. Thus traditional advice is one month before engaging in strenuous muscular activity. Cardio activity may be ok earlier. Some appendectomy incisions created in a manner designed to protect muscles & may speed recovery. Check with your Doc. Hope this helps.