The Adidas_1 was a running shoe made by Adidas, introduced in early 2005. It was the second general consumer sneaker to incorporate a computer (Adidas Micropacer in 1984 was the first). The shoe suffered reliability issues with many being sent back for repair, which initiated the introduction of an improved generation shortly after the release of the original shoes, which was called Intelligence Level 1.1. The shoe was later discontinued, and the official site http://www.adidas-1.com now redirects users to Adidas's web page. The shoe was later followed by the Adidas_1 Basketball Shoe.
Requiring three years of development prior to release, the shoe adjusts itself after each stride, using a motor in the middle of the sole. The motor turns a screw, which in turn lengthens or shortens a cable, changing the compression characteristics of the heel pad.
The shoe typically costs $250 in the U.S.
The changes are guided by a sensor in the heel, which determines how much the heel is compressed on each stride.
The shoe is battery-powered, and lasts for approximately 100 hours of running.
On 25 November 2005, Adidas released a new version of the Adidas 1.
There is an increased range of cushioning and a new motor with 153% more torque in the IL 1.1 upgrade.