Just thought I'd do a quick blog to clear up some of the confusion surrounding core strength and stability.
First off, what exactly is your Core? The Core muscles are taken to include those of the trunk - abdomen and back, which work in combination to help stabilise and support the spine
There is a great video on Youtube by Prof. Paul Hodges, which briefly summarises the issue nicely. You can view it here. I completely agree with what he talks about and the point I am going to make very much echoes his sentiments.
I believe that that core stability is about 'optimal control' as Prof. Hodges puts it so nicely, and for me this comes down to motor recruitment of the appropriate tissues and the correct percentage of motor recruitment/control.
I have in the past taught core and mobility classes for gym goers, namely crossfit participants, and the analogy I used to get my point across about core stability was simply the act of holding a cup of tea or coffee.
Quite simply to hold the cup of coffee the brain has to control the body so that the arm hand and fingers can support the weight of the cup. So there is motor recruitment of finger flexors, forearm flexors, biceps, rotator cuff muscle, deltoid etc. Now does the percentage of contraction of these tissues need to be of a maximal effort? Are we stuck rigid trying to hold on to the cup for dear life. One would hope not. We have over time from a young age naturally learned to enact the appropriate amount of energy to hold that cup.
When we go to drink, the arm moves easily to bring the cup to our mouth. This requires further motor recruitment/control and slightly greater effort to perform. Again, this movement is done with ease and done smoothly and efficiently as it has been learned from thousands of repetitions of the same pattern of movement over time.
So this for me is where the issue people have with 'core stability' is, in that they have lost or maybe never had the ability to recruit the appropriate musculature. And I know when it comes to core stability that it's a team game in terms of muscles and that one isn't necessarily better than the other and they should ideally work in harmony. But people do have imbalances and need to address these issues first, i.e recruitment of deep core musculature. This has to be learned and that can be a difficult task for a lot of people including athletes and it can take time.
The second issue is that people have no idea that the effort required by these muscles is relative. And this is where everyone falls down. It has practically resulted in an industry in the fitness world being created as a result of the confusion. People assume you have to be hugely strong to have functional core stability. Not true. It doesn't require a maximal effort to bend down and pick up a ball. It requires the appropriate amount, to be stable and balanced while still moving freely. If a person was to squat or deadlift a heavy weight, than that would require a greater effort relative to the amount of weight being moved, but still maintaining balance and freedom of movement.
This is where the difficulty lies in that for most people this takes time and effort as a lot of repetition is needed to perfect core stability and to find the right balance for them to be functionally stable. And time and effort are 2 commodities that people do not give up easily. As Prof. Hodges alluded to we have good ideas and practices that are proving effective but we can be better and we are still discovering better practices through research