Flexibility and mobility have been popping up in training articles, discussions and blogs throughout the web as of recent. The popularity of Cross Fit, outdoor boot-camps, and circuit style classes has created an onslaught of research and articles featuring “The importance of movement” within your exercise program. The only error that I observe is how some interchange these two terms. They are related, but very different. Flexibility is defined as the ability to flex, extend, or circumduct a joint through its full range of motion (ROM). To put this in simpler terms, flexibility is the lengthening of tissue. Mobility is the ability to actively move a joint through its full range of motion, under control. Mobility also requires an element of strength. Internationally recognized physical therapist Gray Cook created the functional movement screen (FMS) to analyze and chart movement patterns. This 7-point screen allows you observe inefficiencies of movement, existing or future possible injuries, and asymmetries someone may have. Gray is always clear to state that “the FMS is a screen, not a test”. It’s through corrective exercise work that you can “clean up” the mobility issues. Sometimes flexibility work can improve mobility, but not always. Sometimes the problem is more muscle inhibition. Mike Boyle once stated that “exercise should look good”. “If it doesn’t look pretty, there’s probably something going on”. When addressing mobility we need to discuss the ankles, knees, hips, shoulders, neck, elbows, wrists, and fingers. The reason that I chose to write this article is that I observe many people prioritizing flexibility with passive stretching with the goal of improving mobility. It’s my opinion, that someone can have average or better than average flexibility with poor mobility.
Mobility exercises increase the flow of synovial fluid within the bursa. This fluid “washes” and “greases” up the joint. There isn’t any blood supply to the joint and nourishment is provided solely by the synovial fluid. More importantly, all waste products are flushed out by this fluid. Salt and calcium deposits can frequently create impingements within a joint, greatly affecting range of motion, leading to faulty movement patterns and eventually injury.
I couldn’t discuss flexibility and mobility without mentioning stability. These three work together. It’s sometimes a person’s lack of stability that will affect their mobility and/or flexibility. Boyle states that your body is like a “stack of blocks starting at the ankle and working their way up.”
· Ankles- mobile
· Knees- stability
· Hips- mobile
· Lumbar spine- stability
· Thoracic spine- mobile
· Cervical spine- mobile
Here’s a common scenario. The ankle is in-mobile, and therefore creates knee pain because the knee compensates for the lack of ankle mobility. However the knee is stability joint. This forces the hip to be a stabilizer, but the hip should be mobile. This creates a change in the hips by becoming in-mobile. Next up are the glutes, which become tight and shortened. That’s how mobility can affect stability, which can affect mobility, which in return, will affect flexibility. Hopefully, I cleared things up and didn’t confuse you more!
In closing this is what I recommend. Use dynamic flexibility coupled with bodywork (i.e. foam rolling, massage) to improve muscle length and flexibility. Mix in joint mobility exercises to engage joint range of motion and mobility. Finally, incorporate balance and stability exercises to strengthen the knee and core (lumbar spine). I know, it sounds like a lot, and it is. Remember, Rome wasn’t built in a day. By following this process you will address flexibility, mobility, and stability. It’s my opinion that all three are important. Good luck, and see you in the gym.