Truth: A person can be strong enough to lift 500 pound from the floor, but still throw out their back tying their shoe!
***How does this happen? – WHY does this happen?***
The answer lies in the difference between the ability to brace and the ability to stabilize. While both offer protection by preventing unwanted or unsafe movement, there are many differences!
Bracing is crucial and involves locking down entire regions of the body to prevent any movement…like when you try to lift something you know is heavy (like the example mentioned above) and you stiffen your trunk. Here are some of the features of bracing:
- Stiffens the outside (shell) of the trunk or extremities temporarily
- Prevents too much bending or straightening
- Uses big muscles that usually move the body
- Costs a lot of energy
- Reliable for a few seconds without training
- Cognitive process – you need to be aware of the need to brace beforehand
- Unable to prevent aberrant sliding of the joints surfaces (shearing)
There are some obvious drawbacks of bracing, which is why individuals without an efficient stabilizing system can have major problems in seemingly harmless situations (like the example above). So lets dive into Stability…
Unlike bracing, stabilization allows for movement while it is actively offering protection. This is particularly useful during any movement that is not maximal in nature (most things!). Features of an efficient stabilizing system (aka the “core”) are:
- Fires automatically and before movement occurs – you don’t have to think about it
- Contractions are subtle – you cant usually feel much
- Uses small muscles are deep and close to the joint – they don’t need much strength to do their job well
- Reduces the energy cost of movement – this means you’re more effiecient
- Prevents shear – protects cartilage, discs, ligaments, etc from stress
- Reliable for minutes or even hours of activity
- Exists throughout the body – not just in the trunk!
So, since the bracing system is really only used during maximal activities, why don’t we just use our Stabilizing system?
….and while we are on the topic, what is the stabilizing system? The answer to those questions in our next post: “What REALLY is the Core”
-Dr. Justin Sullivan, PT, DPT, CFMT, OCS, CSCS