Founded by brothers Dennis and Randy Keiser in 1977, Keiser Corporation manufactures fitness equipment in Fresno, California, using its pioneering pneumatic resistance technology to train strength and speed without the inertia of traditional weights. The company’s American-made machines serve athletes, tactical teams, rehabilitation specialists and older adults, while its M Series indoor bikes connect to digital tools that capture workout data. Keiser also supports its equipment with trainer education, performance testing and U.S.-based parts and service.