Basically it is our ability to FEEL a muscle working and properly engage it when it needs to work.
Sitting where you are right now reading this, think about tensing your abs hard.
Your ability to tense that muscle HARD and quickly is a demonstration of the mind-body connection.
That may "seem" easy...
The problem is, there are a number of muscles we don't have as easy a time recruiting, especially as they have to work together with other muscles during a compound movement.
It's why you may only ever feel your biceps during back exercises. Or you may feel your neck during push ups.
Or even why, no matter how much you try to work on your back strength, you can't achieve that first full pull up.
Because our daily rounded-shoulder, hunched posture has disrupted that natural communication and proper recruitment patterns, we need to start our workouts with small, isolated activation moves!
We need to do activation moves that are more isolated movements that create a pump and really allow us to focus on the muscle working. They are often done for higher reps with lighter loads.
If we can re-establish that mind-body connection using these activation moves, we can not only avoid injury, but make sure those muscles are getting worked as they should.
We can then use a combination of heavier lifts to create muscle tissue damage AND higher volume, lower rep moves that create metabolic stress, aka that pump or BURN, to build the lean muscle we want!
We need to start small and finish BIG with those compound and hybrid movements to work more muscle groups at once and get better results in less time!
But we need to START with those small moves to improve our mind-body connection FIRST!