Bullworker

Bullworker is a product and fitness company that specializes in isometric exercise, that is the static contraction of a muscle without any visible movement.

It consisted of three sleeved, spring-loaded, telescopic cylinders in the center, with two hand grips affixed at the outermost ends.

The patent states: "The invention consists essentially in the novel construction and arrangement of parts whereby spring controlled telescopic members are embodied in an exercising apparatus in a special manner more particularly described hereinafter.

The objects of the invention are to devise a portable exercising apparatus particularly for the development of the chest and arm muscles, suitable for both old and young persons by reason of the interchangeability of the resilient member and generally to provide an exercising apparatus to be operated by the hands and arms, simple in construction, cheap to manufacture, durable and interchangeable as to its parts".

A further object is to provide such an exerciser with a degree of adjustability so that as the user's physique improves the effort he has to exert may be increased.

[3]In the 1950s, German scientists Dr. Erich Albert Müller[4] and Theodor Hettinger[5] "observed that contractions involving less than about one third of maximum strength do not train the muscle.

[8] In the 1960s, professor James A. Baley put isometrics to the test with a class of 104 college students at the University of Connecticut.

[9] In the early 1960s, Gert F. Kölbel used and enhanced the devices of Pons and Chapman to create the Tensolator which became the Bullworker, a portable home fitness device and the seven second isometric exercise principle for the fastest strength gains, using both contraction and extension movements involving range of motion for all the major muscle groups, into one lightweight and compact fitness tool at a price everyone could afford.

A further object is to provide an exerciser which the user may manipulate with his hands and feet and may also support against the floor, wall or ceiling of a room.

[10]The original Bullworker device consists of two sleeved, spring-loaded, telescopic cylinders in the center, with two hand grips affixed at the outermost ends.

It is another object of the invention to provide an exerciser which gives a greater amount of contraction for the same initial length of telescopic system.