Muscle balance

Hey Mike, First, thanks for the great articles and workouts that you’re posting they have been very helpful. I started working out again about 2 ½ years ago and I noticed I had some imbalance in my upper body. I didn’t think it would take to long to remedy that but now that I am making more muscle gains it is becoming a little more noticeable to me. What are some tips or techniques to help with balance?