Decade or so ago sports shoes manufacturers made claims for their products which would include how their shoes protect against shock generated by contact with the ground. Many of these claims related to patented materials which were strategically incorporated within the shoes themselves. Now advertising is less likely to contain these claims as scientific research has shown more often than not such addition to shoes are more likely to contribute to injury than prevent them from occurring. Credible Australian research would indicate sport shoes with air pockets in their soles could be leading to sports injuries. Basketball players were found to be four times more likely to suffer ankle injuries when they wore trainers with air pockets in their soles. The ankle injury rate was 3.85% per 1000 of the participants. Failure to warm up properly before competition was also a factor likely to increase injury and players with a history of previous injury were more likely to suffer a reoccurrence. Over half of those injured did not seek professional help. An independent Australian study of basketball players previously reported ankle injuries accounted for the greatest, single reason for missing play. Cells are in the heels and soles of sports shoes have been thought previously to provide worthwhile cushioning to the athlete. The report's authors suggest the air cells may make the rear foot less stable, increasing the risk of twists and sprains as players jump, turn and land. Compressed air is used in shock absorbing systems such as air breaks in big trucks. The air is allowed to evacuate slowly under pressure, and then returned by pumping it back into the cavity for the next impact event. Unfortunately this is not practical in terms of shoe construction and whilst many of the manufacturer’s claims are supported by laboratory studies, these do not always translate into practical applications in life.
In the 1990s there were several shock absorbing heels patented for comfortable business and dress shoes. The VectraSense Think Shoe simply called the Raven Think Shoe was designed by its inventor Ronald Demon. The Raven has a small computer embedded in the sole of each shoe which senses the difference between running and walking. Within 2 seconds, the shoe adjusts using an inflatable bladder to meet your new footgear requirements, according to the manufacturers. By changing the heel ground interface greater shock resistance is available with high peak heel strikes during running (up to middle distance) then slower pace reverts the shoe heel back to normal. The shoes require "AA" batteries but future plans are being made to power the system by some other means.
On the topic of yester-year wearable technology.
The Dada Sprees Supreme athletic shoes had a "spinnah" built into the outside wall of the shoe just above the ankle. When pressure was placed on the heel as with walking or jumping the spinner moved. The shoe was created when Dada Supreme partnered with NBA player, Latrell Sprewell . The Sprees enjoyed a certain vogue among members of the hip-hop community but now are confined to collectors.
Parasitic Power-Harvesting in Shoes?