PART 6: The core in weightlifting and athletics
So far I’ve defined the core, taught you how to control it, instructed you on how to manage it, and outlined how to properly perform core exercises that are specific to you as an individual. In the last part of this series, I will discuss how the core applies to athletics and weightlifting. Until now, all the discussions have solely been about the core, controlling its position, and making it work dynamically as it should for specific core exercises; what about the transfer to higher level activities? How come some people say dedicated core training isn’t necessary because they squat and lift heavy? How come some people never do dedicated core training, but are good at sports and lift relatively heavy weights?
These are all great questions and the starting point to answering those lies in the function of the core specific to our movements, sports, or endeavors. I pointed out that the core is designed to brace you while stopping motion from occurring in the spine. The spine is a stack of vertebrae that is responsible for handling load, shear, and rotations forces yet simultaneously allowing us to move, breath, and perform activities. Evaluating the necessary roles from a strictly passive standpoint (meaning just thinking bones and ligaments), the spine would be pretty poor at handling higher forces. This is where the dynamic system comes into play. As McGill points out, “Analysis of the muscular system, together with its associated fascia sheets, reveals a clever guy wire system that creates balanced stiffness eliminating the possibility of buckling and injury.” The better control and better guy wire system you develop, the more stiffness you create and the more forces you can withstand without buckling.
The simple answer to how core plays into athletics and weightlifting is force transfer. “Proximal stability enhances distal mobility.” We’ve all heard it or something along those lines, but do you know what it actually means and how to use it to you or your client’s advantage? McGill points out a great example of how proximal stiffness improves athleticism:
Consider the pectoralis major muscle, which attaches the rib cage at its proximal end, crosses the shoulder joint, and attaches to the humerus of the upper arm at its distal end. When muscles contract they try to shorten. Consider the specific action here: the arm flexes around the shoulder joint moving the arm from muscle shortening at the distal end. But the same shortening also bends the rib cage towards the arm at the proximal end of the muscle. Thus, simply using the pectoral muscles would not result in a fast or forceful punch. Now stiffen the proximal end of pectoral muscle attachment—meaning stiffen the core and ribcage so it cannot move. Now, 100% of pectoral muscle shortening is directed to action at its distal end, producing fast and forceful motion in the arm. In the same way, a stiffened core locks down the proximal ends of the hip muscles producing faster leg motion. A loss of core stiffness causes the torso to bend when sprinting, and a loss of speed.
Let’s look at this in a physics point of view for a second. When analyzing movements in physical problem, physicists use force vectors. Vectors are geometric objects that have magnitude and direction and can be added to other vectors arising from the same situation. Where the heck am I going with this? If you take the movement and break down the forces occurring at every joint, you will come up with a resultant vector that has magnitude and direction (after a very lengthy and coffee filled morning). Here is a picture showing basic vector algebra:
Now apply these principles to the squat. If a physicist were to break down your squat max attempt, you’d want your resultant vector to be as big as possible and in the vertical position (because we want the bar to go straight up). Every vector that you demonstrate that isn’t in the vertical direction is taking force away from your resultant vector (meaning you are losing pounds off the bar for every slip in technique you have). If you cannot stiffen your core and spine enough to handle the load, then as you break the movement down joint by joint, you will realize how many vectors emerge that chip away at your resultant vector. Rewind back to anatomy now. “The spine loses its load bearing strength as it is bent more away from its neutral posture (McGill).” If you cannot stabilize the optimal position as I discussed, you will lose force during the movement trying to maintain non-optimal joint positions, and thus lose overall force output (lift less weight).
Now that you understand some science behind the saying, here’s how you translate it to your weightlifting or sport. Shinkle et al studied the effects of core strength on the measure of power in the extremities and found that static and dynamic medicine ball throws were significantly correlated to performance measures such as the bench press, squat, and 40 yard dash. They concluded that an athlete doesn’t compete statically or in 2 dimensions or just on 2 feet therefore they cannot be trained in only those modalities. As an athlete you need lateral stability (i.e. suitcase carries), rotational stability (med ball throws), and single leg stability. McGill describes another very practical example:
Consider a 340-pound National Football League (NFL) lineman who is strength trained in the weight room on Olympic-style lifts and power cleans. His coaches believe he is well trained. Yet the athlete has back pain that limits training. Measuring his cutting speed, the ability to take five fast strides forward, plant a foot, and cut to the right, reveals his great weakness and strength imbalance. The pelvis drops on the swing leg side and the spine bends laterally. He reports a twinge of pain. All of his strength training has been performed with two legs on the ground. All of the pulls, lifts and presses never trained the core in 3-dimensions. The weak link is limiting his performance and causing stress and pain. Addressing this with loaded carrying exercises produced more lateral spine stiffness in his core. His pelvis and spine produce appropriate proximal stiffness (proximal to the hip joint) so that more velocity of all of the muscles that cross the hip joint works on the distal side of the joint resulting in faster leg speed. Further, the spine does not bend, the stress concentration at the joint is eliminated and the pain is gone.
Incorporating exercises that enhance these aspects of the sport will improve your athletic abilities. On the contrary if that athlete does planks, side planks, cable rotation exercises, they will have marginal improvement because they have lost the element of specificity. As a powerlifter or weightlifter, the lateral and rotational stability is not nearly as important to you. Your anterior and posterior stability should be prioritized. Does that mean neglect lateral and rotational stability? Absolutely not, the focus of your core training should lie elsewhere.
That wraps up the blog series “Everything you need to know about the core.” There are 6 pieces to the series and I hope you enjoyed all of them. Understanding and properly utilizing this content will help you excel very quickly and achieve your goals faster than you imagined. Subscribe to my website to get weekly updates on new content. In the coming weeks I will talk about the 4 major sources of everyone’s back pain, why everyone should do lumbar rehab during active rest phases, things you’ve never thought about when making your warm-up, and mobility requirements for Olympic lifting and common limitations.
References
McGill, S. (2014). Why everyone needs core training. Retrieved 04/14, 2016, from https://www.nsca.com/Education/Articles/Why-Everyone-Needs-Core-Training/
Shinkle, J., Nesser, T., Demchak, T., & McMannus, D. (2012). Effect of core strength on the measure of power in the extremities. Journal of Strength and Conditioning, 26(2), 373-380.