"Core", "the core", "my core", "I'm going to work on my core"...etc, is also known simply as your trunk. I believe I've mentioned this in a prior post(s), but the term core is a very generic term that was created mainly for media and advertising while introducing a new concept. This concept would look something like this - NOW at blah blah fitness, our trainers specialize in Core Fitness!!!!! (like no one has ever worked on their trunk, back, stomach, and hips before) This is available to the first blah blah and is only available for blah blah time at blah blah price!!!! Core was a media driven word to sell what you were already doing. Media was also playing on your lack of knowledge on what "core" strengthening was/is. It was also an easy term for trainers to use as they didn't know themselves exactly what the core consisted of. So, did I make my point. Physical therapists, at least the ones I hang out with, really really hate the word "core". My dislike for this word might be showing some in this post. Let me tell you what your core really is!
When speaking of performing core strengthening, the parts of the body up from the tailbone to the first thoracic vertebra are the top and bottom of your core. The lateral aspects of your core would consist of the hip joints up to your shoulder complex or shoulder joint. So, if one were to isolate their core, it would be as if strengthening the following:
- Trapezius and lower neck
- Shoulder complex posteriorly and anteriorly
- The upper, middle, and lower back. The back is then broken down in to the upper, middle, lower trapezius, the upper, middle, and lower rhomboids, the latissimus dorsi, the spinae erector muscles of which there are several layers of these...oh crap, you get the picture!
- Chest - includes the pec minor, pec major which is then broken down in to the sternal fibers and clavicular fibers, etc, etc.
- Abdominals which consist of the rectus abdominis, the obliques, and the transverse abdominis.
- The gluts which includes the gluteus maximus, gluteus medius, and the gluteus minimis.
So, to answer the question does core strength help with resolving plantar fasciitis, well yes! Here's the catch. You'll need to know which part of your "core" to strengthen. It will also help to know what part of your core is weak or what muscle groups (agonist and antagonist) that are not balanced proportionately and are subsequently contributing to leg, foot, and ankle injuries.
Here's a hint! Typically, the hip abductors and hip rotator muscles are the suspect muscles. I can not emphasize enough how important the mechanics and strength in your hips are when it comes to controlling how your foot strikes the ground and then leaves the ground especially when running or performing dynamic and ballistic type of activities.
Another point that I have to really emphasize to people is how important it is to step purposefully. This takes practice, but over time, your gait changes without even thinking about it. Stepping purposefully begins at the hip. Advancement of your thigh occurs first in the gait cycle. The mechanics of gait flows down your lower extremity in a chain reaction. The better you control this reaction, then the more purpose you'll have in your gait, and finally the less chance of a breakdown in the leg or foot.
When running or walking, just slinging your foot forward is treacherous! Letting your heel slam first followed by your forefoot and toes slapping the ground is not a controlled nor an energy efficient manner of running.
Strength in your hips will absorb shock and impact from the heel or mid-foot strike. Strength in your hips can contribute strongly to limiting the amount of foot pronation during the single leg stance phase during running and walking. Too much pronation through the foot under vigorous and heavy loads can easily contribute to plantar fasciitis, the development of bunions, and tibialis posterior tendonitis!
So, in summary, it is extremely important to add in exercises that focus on improving hip strength especially with hip abduction and hip external rotation. These muscles change the mechanics at the knee giving it more support. With improved knee mechanics, there is less external tibial torsion or rotation outward which then in turn leads to improved mechanics at the ankle joint or talocrural joint and then the subtalar joint. If you are able to maintain a more neutral subtalar joint, then there will be much less stress on the intrinsic muscles of the foot, the plantar fascia, and finally much less chance of plantar fasciitis!
Try this at home to see how your hips feel when walking more on the outside of your feet vs. letting the arch of your foot fall. Most likely you'll feel a quick onset of muscle tiredness in your hips when doing this. If you do experience a quick onset of muscle fatigue, then this is a good indicator that you could benefit from some cross training with emphasis at the hips!
Whew! Please feel free to email with any questions or concerns!
Happy Bipeding!
Brad Senska, PT, DPT, BS, ASTYM.
bradsenska@yahoo.com