Anatomy

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Core Muscles

Critical to my approach to golf fitness are the core stability muscles : Transverse abdominus (the "corset" muscle which wraps around your lower back) and multifidus - located in your lower back. A combined contraction of these two provide your stability - decreasing your load on the lumbar spine, protecting the joints of your lumbar spine, and providing a bracing force from which your trunk rotators can generate force. The trunk and shoulder rotating muscles are obviously important, Latissimus dorsi, lower trapezius, power the trunk turn while subscapularis and infraspinatus are the shoulder rotator cuff muscles requiring exercises. There is evidence of a combined approach of back muscles giving greater strength than either alone will produce - of great interest is Latissimus dorsi combined with gluteal muscle gluteus maximus - the so called posterior oblique sling. Posterior longitudinal sling is erector spinae with the hamstring muscle biceps femoris. The anterior sling are abdominal internal oblique combined with adductor longus and the lateral sling gluteus medius combined with adductor longus. In generating power with stability - perfect for a golf swing understanding the interrelationships of these muscle groups provide an exercise program with is effective. Look later for sling exercises.

Many people have now heard of the "core stabilizers" - a group of trunk muscles that act to reduce the compressive loading on the lower back - their importance in correct lifting was the reason they are part of a physiotherapy program for lower back strengthening. As has been described the forces acting on your lower back when swinging a club are about 800% of your body weight - it is vital therefore you learn to activate your trunk stabilizers - firstly where are they? If you put your hands on your tummy, thumbs under your ribs, little fingers above your pubic bone - where your hands are is where your transverse abdominus is - except that the muscle actually is three layers below your skin, and wraps right around your body - creating a "corset" type muscle. The first picture - from the front and the second picture - from the back demonstrate this muscle.

The muscle is NOT the one going "up and down" over the tummy - that one is rectus abdominus, exercise that and you will get your "six-pack" look - you can exercise that muscle by doing tiny sit ups, but this muscle will not protect your spine, in fact the sit ups can be BAD for your back, anyway lets concentrate on transverse abdominus - it continues around the back to connect with the spine itself - and also the thoracolumbar fascia, which is where the story really gets interesting, but more of that later.

Viewed from the back, as fibers of transverse abdominus contract it creates a corset effect around the entire trunk, pulling the fibers of the thoracolumbar fascia giving support for your lower back.

As the thoraco-lumbar fascia contracts it also will contract the smaller, deeper muscles of the back giving you the required dynamic stability. Understanding this - and knowing the correct way to strengthen and to get the muscle to contract will place you in a dynamically stable position. The muscles of your lower back will be activated and the back will be supported - as it never can be in any brace or apparatus applied to your back, this activates the stabilizers IN your back. The connection between the thoracolumbar fascia and the transverse abdominal muscle can be improved with exercise. The thoracolumbar fascia actually disperses load around the back - because of its unique layering of muscle fibers.

Of note, when most stomach muscles are contracted, you will bend forwards, as in a sit up, owing to the direction of muscle fibre, however, the direction of transverse abdominus will not allow joint movement when it contracts (you cannot pull your hips together). The muscle fibres run across the tummy, however they wrap around the skeleton, which gives them the "corset" like action.

These muscles are constantly active at a very low level, and research concerning these muscles is being done with regard to reducing strain and loading on the skeleton. Areas such as the shoulder have these muscles which much research has been done, called the rotator cuff muscles, the knee is being researched with interest to a small muscle called vastus medialis, back researchers are looking at the function and strength of transverse abdominus and multifidus.

These muscles are very deep, and result in little to no obvious movement, which makes exercise difficult. It is also necessary to ensure that the CORRECT muscles are being strengthened in the CORRECT manner. A very exact exercise regime is required. Knowledge of the anatomy - exactly WHERE these muscles are assists in your exercise of them.

The muscle must be contracted very slowly, it is easy to "cheat" and make other muscles do the work of your "corset transverse". Initially it is important that no movement of your trunk takes place, if it does it means you have substituted other muscles - your oblique abdominals, your hip flexors or others. These other muscles will not give you the protection required. If you see "crease marks" around your belly button, or going down towards your belly button YOU ARE CHEATING. You should not see a hollowing out under your rib cage either - if you do you are contracting the oblique abdominals, that's OK but its obviously not contracting transverse abdominus. Also be aware that the intensity of exercise NEEDS to be very small - some latest research shows that at intensity levels of 1 - 3 % of your maximum effort voluntary contraction (your MVC) is all that is required - previous research indicated that levels of about 10 % is required - anyway if you are working hard you are not working the muscles you want to work.

There is a very deep set of muscles in the back which also require conditioning. If you have experienced back pain, then these muscles have lost condition, sometimes they may have lost size (atrophied) and strength. To exercise these muscles, again, no movement should take place. You must "feel" the contraction, it must be very slow. It is not easy to contract either muscle group - transverse or multifidus, without skilled instruction and feedback. This is the handout I give patients who are learning how to activate their core based on the work of Prof. G. Jull from Queensland University Physiotherapy Department.

This page owes its existence to the generosity of Primal Pictures, in allowing me to copy from their "Interactive Functional Anatomy" CD to show the location of most of the muscles I mention throughout the website. If you want you can order the CD itself and learn about lots more muscles, contact - sheila@primalpictures.com, and ask for your copy, mention my web site and I'm told a huge price reduction will be yours.