how to warm up legs with leg swing?

the warm-up section of an exercise is more about lubricating the joints and adding flexibility to the ligaments and tendons compared to the muscle itself. although you need to warm the muscles up as well prior to training, leg swing is not the exercise for that. make sure you grab on something to control your balance and be able to go through a good range of motion. do not fatigue yourself as well, just two sets of 10-15 reps for each side and each variation(front and back, and side to side) is enough.