By Caitlin Alexander, PT, DPT, CAFS
There's a lot of talk these days on the topic of 'mobility' in terms of sports performance and injury prevention. Runners are always looking for ways to improve performance while simultaneously avoiding those annoying overuse injuries. While mobility is one of the most important aspects of sport, it ties heavily into stability. You can't have one without the other. Mobility without stability and vice versa can lead to subpar performances, poor movement patterns and injuries. This leads us to the topic of MOSTABILITY = mobility + stability. Mostability is a term coined by Dr. Gary Gray of the Gray Institute to blend both elements to complete a desired task (i.e. running).
MOBILITY = the ability of your joints to move through a given range of motion
STABILITY = the ability of the body to maintain postural equilibrium and support joints during movement
There’s a reason why we feel tightness in muscles or joints. Our perception of this tightness is not necessarily related to an overworked muscle and does not always mean that we should stretch it. But rather, the body’s nervous system is telling you that there’s instability in that region. Instability signals the brain and nervous system to put the brakes on because it feels threatened. It does this by borrowing stability from somewhere else to provide a sense of security. This is called compensation. This compensation is the tightness that we feel.
As the Gray Institute says:
“Just as important, but not as obvious is the 'mostability' of the pelvis when our foot hits the ground in running. At ground contact, the posterior-lateral muscles of the hip have a large role in decelerating the motions of the hip, knee, and foot created by gravity and ground reaction force. These muscles need the pelvis to be a stable base from which to generate force, but the pelvis is moving. So again, both stability and mobility are necessary. During running, the one foot will be in the air when a stable yet mobile pelvis is required. How does the pelvis remain stable while it is moving without the connection to the ground? The mass and momentum of the swinging leg, trunk, and arms all contribute to the ability of the pelvis to have 'mostability'.”
So how can you incorporate mostability into your routine? Below is an example of an exercise that we use at BUILD to help runners achieve dynamic single leg strength, stability and mobility at the pelvis.
REVERSE LUNGE with STEPOVER
The hip joint is a dynamic joint that can move in all 3 planes of motion. This exercise is great for runners in that it three dimensionally combines single leg balance, stability and mobility all in one. The focus should be on gaining mobility through the hip joint of the standing leg, so be sure to really open up your trunk, as shown in the video below. Performing the exercise barefoot may be more difficult but will yield better proprioception integration of the foot and ankle. Try it with body weights or with a dumbbell out in front for added trunk and shoulder recruitment.