A rotation structure includes a main body, two bearings mounted in the main body, a mandrel mounted between the two bearings, a rotation member having a first end connected with the mandrel, and a weight mounted on a second end of the rotation member. The rotation member is situated at a center of the mandrel and is perpendicular to the mandrel. The rotation member and the weight have a total length smaller than a radius of the main body. Thus, the weight is rotated in the main body without producing sound so that the main body is operated in a noiseless manner and will not produce noise during movement.

An apparatus, kit, and method for rehabilitating and/or strengthening the soft tissues of a user's lower arm is disclosed. The apparatus has a first arm with a proximal end and a distal end; a second arm with a proximal end, a distal end, one or more discrete sections therebetween for engaging one or more weights, and a means for providing an audible feedback to the user upon completion of an exercise repetition or a half-repetition; and a hinge in contact with the proximal ends of the first and second arms. The hinge is configured to adjust the distance between the distal ends of the first and second arms, or the angle separating the first and second arms.

Quick release connection for jump rope facilitating exchanging of cables with different weights and diameters on jump rope handles. The quick release connection for jump rope comprises the housing of quick release connection with a locking part attached. The locking part comprises a toothed pawl loaded with a spring engageing with the teeth of the linear rack attached to the cable adapter. The housing of the quick release connection has protruding first and second sidewalls, defining a holding channel including at least one guide rail, for receiving the cable adapter. The linear rack has at least one protruding part that is configured to move into at least one guide rail featured on at least one of the sidewalls of the holding channel. The possible insertion of the cable adapter into the holding channel is only in the longitudinal, reciprocating position.

A device and method may be provided including at least one handle and at least one anchor point. The device may be operable to provide a resistance to a user of the device who fixes the device using the anchor point and pulls on the handle. The device may include a casing; a center rod rotatable mounted in the casing; a cable wound around the center rod and coupled to the handle; and a mechanism mounted on the central rod. The mechanism may be responsive with a centrifugal force to movement of the cable to rotate the central rod. The mechanism may include an anchor coupled to the central rod, and at least one weight connected by a wire to a ring that is movable along the central rod against the resistance of a spring.

Training devices having at least two elastic members connected to a respective end of an inelastic member are disclosed. The training devices comprise first and second handles coupled to a respective one of the two elastic members. The training devices may be used to add various strength training modalities to a cardiovascular workout or fitness regimen. The training device may be provided in the form of a kit including elastic and inelastic members having differing elasticities, lengths, and widths and including removable handles, potentially of differing types.

A apparatus or system defined by a handheld exercise device that includes a weighted body; a handle arranged along a radial axis of the weighted body; and a connector that creates at least one connection between each radially distal end of the handle and a component of the weighted body. The handheld exercise device, in use, minimizes one or more peak forces and rotational inertia acting on a forearm of a user actively engaging the handheld exercise device in motion.

The present disclosure provides a smart weighted hula hoop including a first connecting frame, second connecting frames, and a connecting plate connected with a connecting head. The first connecting frame and the second connecting frames include protruding columns and fastening plates. Each protruding column is snapped on a corresponding fastening plate to make the first connecting frame connected to the second connecting frames. A housing is connected to the first connecting frame. A magnetic sensor is connected to the housing. The first connecting frame and the second connecting frame are connected to sleeves. The bottom end of each sleeve is connected to a respective spring. A fixing sleeve is arranged on each spring. Fixing sleeves are connected to top blocks. A connecting rope is arranged on the connecting head. The connecting rope passes through a lock ring. The lock ring passes through a tapered weight ball.

The present disclosure provides a wrist training device. The wrist training device includes a handle, a central shaft, an adjusting device, and two counterweight wheels. The handle is sleeved on the central shaft. The central shaft includes a thick end and a thin end. One of the two counterweight wheels is fixedly connected to the thick end of the central shaft. Another one of the two counterweight wheels is rotatably connected to the thin end of the central shaft. A hollow groove is arranged on an end surface of the thin end of the central shaft. A plurality of limiting grooves are disposed on a circumferential surface of the thin end of the central shaft. Each counterweight wheels is of an eccentric structure. The adjusting device is arranged on the thin end of the central shaft and arranged in the other counterweight wheel.

Training devices having at least two elastic members are respectively connected to opposing ends of an inelastic member. The training devices have first and second handles coupled to a respective one of the at least two elastic members. The training devices may be used to add various strength training modalities to a cardiovascular workout or fitness regimen. The training devices may be provided in the form of a kit including elastic and inelastic members having differing elasticities, lengths, and widths and including removable handles, potentially of differing types.

A device to strengthen a person's arm muscles through the utilization of a portable device including a handle portion and a weight component with the two components separated by a flexible rod is provided. Such a device allows for the user to grip the handle portion and act as if they are throwing such a handle portion while the weight end moves along an arc defined through the length of the flexible rod. The resultant action is the generation of centripetal force along the defined arc with the reactive centrifugal force providing resistance to the user's arm muscles in a manner that is unique and heretofore unattainable through the utilization of a portable exercise device. The flexible rod component provides at least 1 foot (100 cm) of spacing between the handle portion and the weight portion.