Patent ID: 8162808

Claim:
A curl bar for attachment to a resistance assembly, comprising: a generally cylindrical curl bar body with a long axis, said curl bar body comprising: a left and right generally cylindrical grip handle, adjacent to and spaced apart from each other and with both grip handles parallel to said long axis of said curl bar body, configured to move toward each other when pressed toward each other by a user; at least one attachment yoke attached to said curl bar body, for attaching said curl bar body to said resistance assembly, for providing a user with resistance in a first direction, normal to the long axis of the curl bar body; a compressible section of said curl bar positioned between and physically joining said left and right grip handles, allowing said curl bar to shorten and lengthen against resistance along the long axis of the curl bar, in which said compressible section is a hollow chamber defined in one of said grip handles of said cylindrical curl bar body, with a piston attached to one grip handle and movable inside said hollow chamber in a remaining grip handle, for providing resistance to lateral movement parallel to the long axis of the curl bar, by compression of air in said hollow chamber by said piston; an air release valve functionally connected to said hollow chamber, for allowing air to escape from said hollow chamber at a selected rate, for adjusting the degree of resistance to said piston moving through said cylinder, in which said air release valve is a channel drilled in a threaded end cap of said grip handle in which said hollow chamber is located, and is adjustable by turning said threaded end cap.