I’m expecting some controversy around this blog; of course if you are treating your clients holistically you wouldn’t ignore ANY muscles and I could list another ten that warrant attention in most clients! However in the context of a sedentary lifestyle, some muscles are likely to have more of an impact on the prevention or creation of imbalances, postural issues and injuries. So here is a BRIEF run down, in no particular order.....
Serratus Anterior (SA)
Also known as the ‘boxer’s muscle’ for the way it shows itself on the side of the chest during a jab, this muscle inserts onto the medial tip of the scapula from its origin on several of the ribs. Besides holding the scapula flat against the ribs and assisting with protraction, what’s more important is the Serratus Anterior’s role in scapulohumeral rhythm. It works with the Lower and Upper Trapezius during abduction of the humerus. If the Serratus Anterior is weak, the Upper Traps pick up the load and can become overactive, which in turn inhibits the function of the Lower Traps. During abduction, this causes the head of the humerus to get jammed into the top ridge of the glenohumeral joint rather than pulled down neatly into the socket as is supposed to happen. The risk is that the client is opened up to shoulder impingement injuries as the humerus rubs excessively against the superior labrum.
Gluteus Medius (GM)
Now don’t get me wrong: your gluteals as a whole are extremely important, and I’ve had countless clients where neural activation in this region is next to nothing! The Glut Med however, which originates from the Ilium and inserts onto the femur (on the outside of the hip) is extremely important for pelvic stability. When your GM is inhibited your hip drops which sends your knee rotating medially; this has a detrimental effect on the biomechanics of the leg and increases the general wear and tear of the joint. Furthermore, the dropped hip also plays havoc on the lumbar spine as the vertebra become misaligned which places excessive stress on the facet joints and vertebral discs. Be sure to program plenty of single leg work if you know the Glut Med isn’t firing and ensure your clients’ hips remain on a horizontal plane at all times and their knees don’t buckle medially.
Transverse Abdominis (TA)
The latest statistic I read from the Chiropractors Association Queensland was that 80% of Australians will experience disabling lower back pain at some point during their lives! That is a telling statistic and one I’d believe given the lifestyle choices we make (read: sedentary). Your TA is your human weight belt, wrapping around your torso to support your lumbar spine and much more. Sitting down all day switches it off, need I say more? If your clients are struggling with this one, practice supine and prone drawing the belly button towards the spine. A subtle movement, but SO important.
Vastus Medialis Obliquus (VMO)
The VMO plays a vital role in how the patellar tracks in the patellofemoral grove. If the VMO is weak, the patellar gets pulled laterally by the ITB and Vastus Lateralis and can cause pain in the knee joint due to the increased friction. This muscle also has an interesting length-tension relationship with the Glut Med; they work together to stabilise the leg, hip and pelvis as a whole. If there are VMO problems, there are likely to be issues further up the chain so ensuring gluteal activation and correct leg alignment during movement is critical when addressing the VMO and knee.
Your Rhomboids originate from your upper thoracic spine and insert onto your scapula. Their primary role is to retract the scapula and someone who has an excessive kyphosis will have inhibited rhomboids as they are permanently on stretch. Lack of control of this muscle means the scapula sit in a chronically protracted position. This position inhibits the ideal mechanics of the whole shoulder girdle, and during abduction places the head of the humerus into a vulnerable position in the glenohumeral joint and in danger of gaining injuries such as shoulder impingements, bursitis and so forth. Be sure to release the client’s pectorals before performing activation exercises to help create neural pathways to this incredibly important muscle. By releasing the opposing muscles first it helps to improve the clients ROM and gives them a greater chance to active the correct muscles. This process will at least set your client on the right path to correcting their posture and avoiding some nasty shoulder injuries.
What are your top 5 muscles that you find come up over and over again when you are training clients? Leave us a comment below!
Tristan Hill, Masters of Sports Coaching, author of Lifting the Bar and mentor to Personal Trainers.