>>34691099Endurance is an ability derived from your cardiovascular system as well as your muscles. If you want more endurance then I would not suggest doing anything in the gym, let alone free weights.
Doing cardio, loads of bodyweight exercises, etc. will be endurance-focused training.
If you start doing resistance training (gym stuff) with endurance rep ranges, like 20-30 reps, you will give yourself tendonitis. Which is not good.