Foot Cushioning

CambionŽ visco-elastic insoles and heel cushions are the next generation of orthopaedic shock absorbing shoe inserts. Cambion shoe inserts are designed to protect the skeletal system from the jarring effects of heel strike and redistribute underfoot pressure.

If you've ever noticed, when walking or running on hard surfaces that it feels like someone is whacking the bottom of your feet with a hammer, then you know what heel strike is. It's the shock of your feet hitting the ground with all your weight on top of them. It's much worse when you're on hard surfaces than when you're on grass or bare ground. That's because when humans were evolving, the hardest thing they ever walked on, except for maybe the occasional rock, was the earth itself. It's only in the last 100 years that we began to walk on hard unnatural surfaces.


Modern surfaces, such as concrete, asphalt and floors, are far harder. When your feet land on them, the force of the impact is often more than your system can naturally absorb. The shock travels back up through the body, stressing and eventually damaging joints and causing fatigue. Excess weight, athletics, repetitive activities and standing for long periods can aggravate the situation. The heel strike shock particularly affects your lower skeletal frame --your knees, hips and lower back as well as your feet. In the long run, it can inflict pain, limit activity and in some cases, require joint replacement.


Visco-elastic Polymers Provide The Solution!


Due to fashion trends and cost cutting by manufacturers modern footwear rarely has sufficient cushioning. Most sports shoes which should offer better protection are rarely suitable for work or business use and studies have shown that most sports shoes loose much of their cushioning effect within a short time. For years, scientists have studied the problem and looked for possible solutions. Bio-engineers, orthopaedic surgeons and physical therapists saw that, if they could find a way to place a shock absorber between foot and the ground, the energy would be diffused before it damaged the joints. For those already afflicted, such shock absorbers would help relieve pain and prevent further damage<.


Studies were designed, experiments were conducted, materials tested. The results all suggested that visco-elastic polymers were the optimum materials for underfoot cushioning. These synthetic materials, which are both dense and elastic, proved remarkably able to absorb the shock of heel strike. Taking up less space in the shoe than conventional foam materials, visco-elastic polymers are the most efficient form of underfoot cushioning available today. In fact, you would need up to 15 drug store insoles to equal the cushioning effect of one Cambion visco-elastic insole.


In tests that actually measured the amount of shock that various parts of the body sustained when walking, visco-elastic materials in combination with micro-porous foams showed far greater ability than other materials to dampen shock and reduce rebound. They cushioned the skeleton as the foot hit the ground and instead of kicking back instantly, they dissipated the energy evenly over several milliseconds. That is key to protecting the joints.


Technology Gets Underfoot.


In the last ten years the results of this research have published in numerous scientific papers.* Material scientists have used this information to refine and further develop state of the art polymers to take advantage of this knowledge.

Visco-elastic shoe inserts are now widely available in various forms. They're a little more expensive than the foam rubber shoe inserts commonly sold in drugstores, but they last longer and work better. Even the crudest visco-elastic product is more effective than the best foam rubber insole! But there is wide variability within the field, too. Effectiveness depends largely on the specified visco-elastic polymer used -- they've come a long way since they were first developed -- and on product design.


Although some are sold in sporting good stores and other outlets, the most advanced, most effective products are available through professionals -- physicians, podiatrists, physical therapists, chiropractors, athletic trainers -- who know about the conditions such products are designed to prevent and treat. Some professionals offer their patients complete underfoot orthotic systems. These modular systems allow the professional to modify the insole by adding specially designed pads, wedges and lifts when and where you need them.

The number of applications for theses advanced systems is almost unlimited. They can be used to prevent and treat a variety of problems common to athletes and fitness devotees, older adults, people who are on their feet for long periods. It might be the kind of shock treatment you need.

* Genesis Medical would be pleased to provide therapists with a copy of a review by Dr. Michael W. Whittle "The Use of Viscoelastic Materials in Shoes and Insoles".

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