Everyone usually has a dominate arm that does most of their work. Even if you are ambidextrous, your likely to still have one arm stronger. You see this when you look at the arms of tennis, table tennis and pitchers. There is a definite size difference. Plus with everyday activities, writing, hammering a nail, picking things up, and holding a child with one arm is really when you start seeing the discrepancy in strength and size.
What is the best way to start balancing out your strong and weak extremities?
The best way and simplest way is using Dumbbells. This has been proven over the years as the best way to train. It takes balance and coordination with both arms. When first starting the difference in strength and balance is very obvious. Give it two weeks and you won’t be able to tell the difference.
Sometimes people ask me if they should try doing more reps on the weaker side to balance their arms out. Some people try it. But I prefer using the same weight. It creates better overall body balance, and strength. If there has been an injury then that is different, you need to rehab slowly and consistently to get back to that same level. But it even gets to a point in rehab that you should use the same weight.
Is it possible to also have a strong leg and a weak leg?
Yes, but the difference is not so noticeable, because both legs are used fairly consistently. Where you see the difference is when you jump off of the dominate leg or kicking a ball. Even balancing on one leg can reveal a difference. When trying to balance out your legs an exercise you can use is the one legged leg extension and leg curls work. Lunges are great for legs also.But I don’t like one legged squats; too dangerous.