Jumping stilts or spring stilts are special stilts that allow the user to run, jump and perform various acrobatics. Spring stilts using fiberglass leaf springs were patented in the United States in 2004 under the trademark "PowerSkip", marketed for recreational and extreme sports use. Using these stilts is also called powerbocking, named for the stilts' inventor, Alexander Boeck. Spring stilts are often mostly made of aluminium.
The act of powerbocking is jumping and running with elastic-like spring-loaded stilts. For some it is an extreme sport, for others it is a form of exercise or even a means of artistic expression. The use of the stilts to perform extreme jumping, running and acrobatics is known as 'Bocking' or 'PowerBocking' after the inventor. Generically these are referred to as "power stilts", "jumping stilts", or "spring stilts". The stilts are often referred to generically as bocks or powerbocks, or by their brand name.
Each boot consists of a foot-plate with snowboard type bindings, rubber foot pad which is also commonly called a hoof, and a fibreglass leaf spring. Using only their weight, and few movements, the user is generally able to jump 3–5 ft (1–1.5 metres) off the ground and run up to 20 mph (32 km/h). They also give the ability to take up to 9-foot (2.7 metres) strides.
Jumping stilts were used in the closing ceremony of the 2008 Olympic games in Beijing.
They were originally patented by Alexander Böck, from Germany (European Patent EP 1 196 220 B1 on July 2, 2003, US Patent No. 6,719,671 B1 on April 13, 2004, both with a priority date of July 20, 1999), as Powerskip. Many people also use common brand names to refer to them generically.
Common brand names are: 7 League Boots, Air-Trekkers, Powerizers, Pro-Jump, and Powerskips.
On December 4, 2010 Samuel Koch was heavily injured during the Show Wetten, dass..? during a stunt where he attempted to jump over multiple moving cars in succession. He failed to clear one of the moving vehicles and was left quadriplegic after suffering severe injuries to his neck and spine.
Though similar in appearance, powerbocking is not to be confused with the use of prosthetic devices such as those used by paralympic runner Oscar Pistorius.