Ok i was just wondering if anyone ever had this before, it's been happening to me basically since i started working out. What happens is every exercise i do the left side is always favored more, i feel it more during the exercise and the left side is more sore the next day. for example when i bench press, my left pec i always more sore than the right side, and when i do curls my left bicep always hurts more the next day, and i use dumbbells, same thing with my trieps and shoulders.