Monday, July 27, 2009
That got me thinking how many other people don't understand the importance of balance training? The benefits apply to every day functional living and all the aspects of an integrated training program... so, this is the next blog I'm going to work on. I'm putting it up now so I have to actually do it :)
Stay tuned ...
Thursday, July 23, 2009
Let’s take a quick look at the definitions and then put it all together using a squat as an example …
Agonists are the muscles primarily responsible for a specific movement, also called the prime mover. The bicep is the agonist for bicep curls.
Antagonists are the muscles that oppose or work in opposition of the agonist. The triceps are the antagonist for the biceps.
Length-tension relationship - this is the length at which a muscle can produce the greatest force. If a muscle is lengthened beyond this “optimal length”, it reduces force production. If a muscle is shortened beyond this “optimal length”, it reduces force output.
Synergistic dominance – when a synergist (helper) compensates for a prime mover to maintain force production.
Altered reciprocal inhibition - when a tight muscle causes decreased neural drive to its functional antagonist. Reciprocal inhibition is a normal occurrence. When you perform a bicep curl, the Central Nervous System (CNS) sends a message to the triceps to “relax”. This allows the bicep to contract and perform the curl. If the triceps did not relax the arm wouldn’t move. The dysfunction occurs when the bicep stays in the tight, contracted, or overactive state… this forces the triceps to remain in a lengthened/relaxed state. While in this relaxed/lengthened state, the CNS cannot properly recruit the triceps and it becomes weak. This is when synergistic dominance occurs; other muscles must start performing the work the triceps are supposed to do.
Overactive – muscles that are in constant “shortened”, tight, or contracted state.
Underactive – muscles that are in a constant “lengthened” state. The CNS can no longer properly activate these muscles to perform their function.
Force-couples – Muscles work in “groups” or together to produce movement. The CNS selects muscles to work in “synergy” to reduce, stabilize, and produce force. Muscles do not work in isolation. With every movement, there are muscles working to assist the muscle doing the activity and stabilizing the joints involved. All the muscles working together to produce movement are working as a force-couple.
Intramuscular coordination – ability of the neuromuscular system to allow optimal levels of motor unit recruitment and synchronization within a muscle.
Intermuscular coordination - ability of the neuromuscular system to allow all muscles to work together with proper activation and timing between them.
Synergists assist agonists, or prime movers, during an activity. The front of the shoulder and the triceps are synergists to the chest during bench presses.
Stabilizers work to support or stabilize the body while agonists and synergists work.
Concentric contraction is the shortening of the muscle to produce force. When you perform a bicep curl, the bicep “shortens” as the weight comes toward the shoulder.
Isometric is a contraction where the muscle neither shortens nor lengthens, but maintains its length. This is the main contraction used for stabilization.
Eccentric contraction is the lengthening of the muscle to reduce force. When you lower a bicep curl, the bicep is lengthening and reducing force, or, slowing the movement down.
A popular workout in the gym is the squat.
The agonists, or prime movers, in a squat are the gluteus maximus and the quadriceps. The synergists (helpers) are the hamstrings, adductor magnus, posterior tibialis, and the gastrocnemius/soleus. The antagonist of the gluteus maximus is the psoas (hip flexor).
In this example, we’ll assume the psoas is tight or “overactive”. This decreases the CNS’s ability to recruit the gluteus maximus – a prime mover during a squat. For simplicity of the example, I'm not going to address what's going on with the rest of the body during this dysfunction, as a weak glute and tight psoas has a domino affect on the body.
During descent, as you lower to the ground, the gluteus maximus decelerates (eccentric contraction) or “slows” down this movement.
When the psoas is tight and the gluteus maximus is weak, other muscles must be recruited (synergistic dominance) to perform this deceleration function. The quadriceps and the gastrocnemius/soleus are now required to perform more work to slow down momentum. The compressive forces on the knee and can lead to pain and injury.
During hip extension, as you stand up from the squat, the glutes, quads, hamstrings, and gastrocnemius/soleus all work in synergy to produce force and allow you to stand up. With weakened glutes, the hamstrings, quads, and gastrocnemius/soleus become synergistically dominant, picking up the slack from the weakened (underactive) glutes. This puts excessive strain on muscles that were not designed to perform this function.
It is essential to have optimum length-tension relations within the body prior to performing strength training, cardio, sports or any other functional type movement.
This is the basis of Corrective Exercise:
1. Identify the overactive (tight) muscles and bring them to their optimal length.
2. Identify the underactive (weak) muscles and strengthen them (intramuscular coordination).
3. Perform integrated exercises to retrain the CNS to recruit the proper muscle synergies (intermuscular coordination).
Let's look at the process of addressing this dysfunction. If, after an assessment, we determine the only imbalances are an underactive (weak) gluteus maximus and an overactive(tight) psoas, we could address the issue using the following:
1. Inhibit the psoas with self myofascial release (foam roll). Hold on tendor spot(s) for 30 seconds – perform 2 sets.
2. Lengthening the psoas via a static stretch. Hold stretch for 30 seconds – perform 2 sets for each leg.
Sunday, July 19, 2009
Unfortunately, most of us look like this:
Here's a quick test to determine if you may have a problem. Look in the mirror... do you see the back of your hands? If you do, then you're on a fast track to having shoulder problems - if you don't have them already. When your arms are at your side and your palms face behind you and the knuckles face the front, this indicates your shoulder blades are protracting (moving forward). Pain and injury await you. Slouching perpetuates the problem. Some people spend 5-10 hours a week in the gym building "big muscles". How long are you spending in your chair, slouching, building "shoulder problems"? It adds up and it ends in pain and loss of stabilization.
According to Dr. Gallagher of Gallagher Chiropractic & Sports Medicine Group:
“... in a standing position that there is 100 pounds of pressure placed on each intervertebral disc. Did you also know that in a seated, slouched position that the load doubles to 200 pounds of pressure per disc?”
Over time, there is a gradual increase in the thoracic kyphosis. Structural changes do not occur overnight. This is a result of repetitive postural stress on the kinetic chain. And once this postural distortion takes root and the muscle imbalances exist, one cannot simply “fix” the dysfunction by “sitting up” in the chair. Muscles have become overactive and underactive, pulling the body into this distortion.
This leads to rounded shoulders and a protruding head. What is commonly referred to as The Upper-Extremity Postural Distortion (The Upper Crossed Syndrome).
The probable overactive muscles: Pectoralis Major, Pectoralis minor, Levator Scapulae, Teres Major, Upper Trapezius, Anterior Deltoid, Subscapularis, Latissimus Dorsi, Sternocleidomastoid, Rectus Captious, and Scalenes.
The probable underactive muscles: Rhomboids, Lower Trapezius, Serratus Anterior, Posterior Deltoid, Teres Minor, Infraspinatus, and the Longus Coli/Capitus (Deep Cervical Flexors).
We say "probable" over/underactive because any combination of an over/underactive agonist/antagonist listed above can lead to problems. Without a movement assessment, goniometric measurements, and manual muscle testing, it's difficult to say what combination may be causing the problems.
Static Stretch the Upper Trapezius, Levator Scapulae, Sternocleidomastoid, Latissimus Dorsi, Pectoralis Major/Minor.
The key muscles to address with flexibility and activation are the Pecs (major/minor), Latissimus Dorsi, Sternocleidomastoid, Upper Traps, Scalenes, and Levator Scapulae (the overactive/tight muscles) and the Mid/Lower Traps, Rhomboids, Rotator Cuff, and Deep Cervical Flexors (underactive/lengthened muscles).
That's a lot of muscles firing out of synch. I like to look at the isometric function of the muscles... what stabilization is being lost?
The muscles responsible for shoulder stabilization: Pec Major and Rotator Cuff.
The muscles responsible for scapular stabilization: Pec Minor, Mid/Lower Traps, and Rhomboids (also provides the rotator cuff a stable platform in which to work efficiently.
Stabilization of the Lumbo-Pelvic-Hip complex (L-P-H-C): Latissimus Dorsi
Muscles stabilizing the cervical spine: Sternocleidomastoid, Upper Traps, Scalenes , Levator Scapulae, Deep Cervical Flexors (Longus Colli, Longus Capitis).
The altered length-tension relationship in these areas can cause pain and lack of stabilization during overhead motions, loss of dynamic stabilization of cervical spine, and dysfunction with pushing/pulling movements. This can be noted by shoulder pain during shoulder press, bench press, and rows.
The loss of stabilization in these areas can lead to rotator cuff impingement, shoulder instability, biceps tendonitis, thoracic outlet syndrome, and headaches.
Again, without specific testing to determine exactly what muscle imbalance(s) are causing the problem, a "shotgun" approach to addressing the Upper Crossed Syndrome is as follows:
Self Myofascial Release (Foam Rolling) the Lattisimus Dorsi and Thoracic Spine.
Activation of the Mid/Lower Trapezius, Rhomboids, Rotator Cuff, and Deep Cervical Flexors.
Y-T-A (Ball Combo I)
Chin Tuck exercises
A good exercise library for the mentioned exercises can be found at www.nasmpro.com
- Strengthen the deep cervical flexors
- Strengthen the mid/lower traps, rhomboids
- Stretch the Lats, Pecs, Scalenes, Sternocleidomastoid, Levator Scapulae, and Upper traps
National Academy of Sports Medicine CPT, CES, PES
American Council on Exercise CPT