Through the innovative use of extremely strong aramid fibers and non-newtonian materials, the Graceyfeet Cush material reduces both peak and mean vertical shock, so the highest forces are reduced and you do not feel the vibrations that are detrimental to your game. However, there are vibrational frequencies that do make it through the insole and give you the exact tactile feedback you need to determine what part and how forcefully your foot is contacting the ground.
First, some ground-work...Vibration forces input help us to perceive up from down and position in space. But excessive and repetitive vibrational forces cause pre-synaptic, reflexive, extraneous motions about the joints(1,4,6). A 2002 study using EMG, strain gauge, and plantar pressure mapping found that muscles may lose up to 10% of their strength after 35 minutes of weight-bearing exercise due to reflexive proprioceptive adjustments caused by excessive peak vibration signals at the ankle(6). Also, high peak and mean vibration forces cause reposition sense error and direction error in the low back and trunk(2,3). This means that after roughly a half-hour of sport-related vibrations, there is a 10% loss of functional strength in certain muscles, and a decrease in body positioning and directional accuracy.
Graceyfeet Cush insoles reduce peak and mean vertical forces by 30%-60%. Yes, some of the GRF is not felt, but only excessive ground reaction shock is affected. all other vibration related to temporal and spatial input is preserved. Subjective reports from clients are that kinesthetic control improves using Graceyfeet over shoes alone because they feel like they have more grip and better control of their body position at various moments during their swing. Also their ankles, knees, and back feel better.
The Graceyfeet Cush insole simply allows the vibrations necessary for a specific task to pass through so the sense of "Feel" (perceptive sensory feedback loop) and your "response" (body placement, task execution, muscle strength) actually improves. The plantar pressures are reduced, but your proprioception remains unchanged. Consider the conditions of being barefoot on soft grass; large contact surface area, improved grip, and reduced vertical forces with nothing to impede the skeleton's preferred path of progression. But put a shoe on, and vertical forces rise dramatically over smaller surface areas, muscle activity is very different, and tactile sensation is changed.
Current insole materials have a very small effect on high vibration pressures (5-10% tops). So replace the existing sock-liner with a Graceyfeet Cush insole and the environment within the shoe changes to respond more like barefoot on grass! Contact surface area is increased, vertical forces are dramatically reduced, grip is improved, and the preferred path of progression is retained. All the proprioceptive neuromuscular re-education you gained training barefoot is retained because of the similar "Feel" of Graceyfeet to barefoot on grass.Drop only the vibrations that cause fatigue and inaccuracy, quiet reflexive motions, and your performance will be enhanced through improved accuracy and timing over long duration sport activities.
The Graceyfeet insole smooths out the ride by blocking shock from below and lightly decelerating movement from above. Kevlar attenuates the shock while the medical-grade SRP (the green stuff) minimizes the effects of abstract reflex muscle activities that cause fatigue and disrupt performance.
In essence, it improves performance by normalizing plantar pressures across varying terrain and providing excellent energy return. But as with any new shoe or insert/orthotic, you do have to get used to it first.
Remember, the ability to sense where your foot is in space correlates very poorly with the ability to place your foot in a desired position. The magnitude of your muscular reaction to changes in angular velocity about a joint due to sensory input may be fine tuned when the foot is in a familiar environment and feedback is experienced in a known, controlled range.
Take a look at my blog entry on volleyball court surfaces. Peak performers will practice on the terrain they play on in the conditions they will expect to encounter. Using Graceyfeet in both your daily and your sport-shoes will maintain a symmetry of feel between activities.
Quieting the vibrations through the body allows for purposeful and focused cognitive and physical release.
Learn and adjust skills barefoot.Practice and Play in Graceyfeet.
http://dx.doi.org/10.1016/S0304-3940(99)00302-X, Vibration alters proprioception and dynamic low back stability
Proprioception, gait kinematics, and rate of loading during walking: Are they related?
Proprioception of the Ankle Joint