The present application discloses a standing vertical lower limb exercise device. The lower limb exercise device includes two major pivotal members, a horizontal bridge member that connects the major pivotal members, a stretchable spring, a string member for limiting a split angle formed by the two major pivotal members, and wheels, gears, and shafts to facilitate movement of the two major pivotal members. The stretchable spring and string member are coupled between the two major pivotal members. Wheels are coupled to each major pivotal member.

A fitness device comprises a waist belt configured to fit around a user's waist and at least one resilient leg loop member. The resilient leg loop member has a proximal end movably anchored to the waist belt at a posterior position. The resilient leg loop member has an opposite distal end configured for coupling with one of the user's feet. The fitness device causes a predetermined resistance force to be generated against the user's movement when the user extends the leg loop member beyond its length at rest. In some embodiments, two resilient leg loop members are provided. Methods of using the exercise device are also described.

A breath control device comprising t least one longitudinal tube with a wall with at least a resilient part, wherein the tube is embodied with a proximal open end and a closed distal end, and that the wall of the tube is provided with one or more at least in part active user-controlled closable openings or slits so that the fidgeting device also embodies a breath exercise device.

A portable exercise apparatus in the shape of a square having a handle at either side, which handles are arranged rotatable on spindles such that the user can impart movement on said apparatus without changing his/her grip.

An exercise and rehabilitation bar including a flexing bar, at least one resistance insert, and at least one handle. The flexing bar has a first end, a second end, and a cavity running from the first end to the second end. The at least one resistance insert is removably carried within the cavity of the flexing bar and the at least one handle is removably securable to either the first or second end of the flexing bar.

Provided are apparatuses for augmenting human speed, human-driven compliant mechanisms, artificial limbs to augment human movement, and the like. The apparatuses can include variable stiffness mechanisms including springs that can be configured to selectively store and subsequently release energy generated by human movement. The apparatuses can selectively release the captured energy supplied by the human to provide force and power output beyond the physical capability of the human.

A rebounding device includes a front member, a rear member, and a spring mechanism including a first biasing element and force adjustment assembly. The force adjustment assembly includes a spring element including a front planar surface and a rear planar surface connected at a rounded portion, wherein the front planar surface contacts an inner surface of the front member; a screw housing secured to an inner surface of the rear member, wherein the screw housing includes a longitudinal channel and a bore on an upper surface; a drive screw positioned through the bore and along the longitudinal channel of the screw housing; a threaded block positioned within the longitudinal channel of the screw housing, wherein the threaded block is configured to move vertically along the longitudinal channel, and wherein the rear planar surface of the spring element is secured to the threaded block.

A rebounding device includes a front member, a rear member, and a spring mechanism including a first biasing element and force adjustment assembly. The force adjustment assembly includes a spring element including a front planar surface and a rear planar surface connected at a rounded portion, wherein the front planar surface contacts an inner surface of the front member; a screw housing secured to an inner surface of the rear member, wherein the screw housing includes a longitudinal channel and a bore on an upper surface; a drive screw positioned through the bore and along the longitudinal channel of the screw housing; a threaded block positioned within the longitudinal channel of the screw housing, wherein the threaded block is configured to move vertically along the longitudinal channel, and wherein the rear planar surface of the spring element is secured to the threaded block.

Apparatus (100) for exercising the muscles, comprising an exercising device (1) having a power arm or lever (2), which can be equipped with actuating elements (4) at a first end (3) and, by way of a second end (5), is arranged on a retaining element (6) in a way pivotable about a pivot axis at a first articulated joint (9), whereby a compression-spring element (11) can be articulated, by way of a first end (10), at a first point of articulation (12) on the power arm (2) and is articulated, by way of a second end (13), at a second point of articulation (14) on the retaining element (6), and also comprising a cable-pull arrangement (50) having a cable (60). The cable-pull arrangement (50) of the apparatus (100) is fixed in a releasable manner in a spatial relationship to the exercising device (1), independently of the exercising device (1), by means of a first fixing device (52) and is able to be combined with the power arm (2) of the exercising device (1) by means of a second fixing device (58), so that the cable-pull arrangement (50) is connectible to the exercising device (1) in order for training to take place.

An exercise machine comprises a tension generating device, a translatable arm mount coupled to the tension generating device, an arm coupled to the translatable arm mount, and a cable coupled to the tension generating device via the arm.