A chest protector may include a flexible panel configured to generally conform to a user's chest and abdominal regions, one or more retention elements connected to the flexible panel and positioned to hold the chest protector on the user, and one or more high-friction elements positioned on an anterior outer surface of the flexible panel, the one or more high-friction elements configured to reduce angular momentum, or change rotation, of a ball impacting at least one of the one or more high-friction elements. The high-friction elements may include elements of tacky material, such as one or more dots or other elements of tacky material.

A sports grip alignment device for swinging sports devices is described, such as for a baseball/softball bat, golf club, tennis racket, etc. The alignment device promotes an efficient swing by assuring a consistent grip. An implementation may be secured to the sports device. A rod may extend from a knob end to a barrel end distal from the knob end, the knob end tapering in from an inner side, a right side, and a left side to a point, the barrel end forming a semicircle from the right side to the left side. An implementation may include a convex outer side and a concave inner side extending along the length of the rod. A plurality of knobs may be distributed along the length of the convex outer side. A plurality of slots may be distributed along a portion of the length nearest the knob end in the concave inner side.

Representative embodiments of the present technology include a ball bat in which part of an inner surface of the bat wall has a contoured region including a plurality of radially inwardly curving portions and a plurality of radially outwardly curving portions. In some embodiments, the contoured region is asymmetric relative to a longitudinal center location of the contoured region. In some embodiments, the curving portions are unevenly distributed along the length of the contoured region. In some embodiments, a method of manufacturing a ball bat includes generating a simulated body within a simulation region, the body having a starting geometry that is modified to include less material (less mass) while conforming to displacement limits associated with loads at specified loading locations, among other variables.

A sensor system includes an airbag engaged with the sole structure of an article of footwear, the airbag configured to compress and expand during use of the article of footwear, a force sensor engaged with the airbag and configured to detect force on the airbag based on changes in capacitance as the airbag compresses and expands, a port connected to the article of footwear and configured for communication with an electronic module, and one or more conductive leads extending from the force sensor to the port to place the force sensor in communication with the port. The system may be used with an article of footwear including an upper member at least partially defining a foot-receiving chamber and a sole structure engaged with the upper member.

An apparatus for storing a bat, a bat stand, may comprise a cylindrical body, a base, a ring, and a finger plate. The ring may thread to the top of the body and help secure a finger plate in the interior of the bat stand. The base of the stand may be wider than the body so as to lower the center of gravity and increase the stability of the bat stand. The finger plate may be made of a rubber base supporting a fabric top. The finger plate may have multiple fingers that help to center a bat vertically within the bat stand. In some embodiments, screws secure the ring to the body with the finger plate in between.

A ball bat includes a first bat portion (such as a barrel portion) and a second bat portion (such as a handle). The portions may be spaced apart along the bat's longitudinal axis. A joint connects the first and second bat portions. The joint may be positioned at or near, or centered about, a location of maximum vibration, such as an antinode of the bat. The joint may include a filler material (such as an elastomeric material) at least partially surrounding a rod element. The filler material and the rod element may span a gap between the first and second bat portions. The filler material and the rod element may extend into the first bat portion or the second bat portion. A cover material may be positioned around the filler material. The joint may form a structural link between the bat portions and it may be configured to absorb vibration.

A ball bat may include a handle portion and a barrel portion extending away from the handle portion to an end cap. The barrel portion has an outer wall formed from aluminum and includes at least two and no greater than four inwardly projecting circumferential humps spaced by intervening circumferential valleys.

A baseball or softball bat includes a barrel extending from a handle having a knob. A cap defining a chamber partially filled with gel is attached to an end of the barrel or the knob for dissipating vibrations created when the bat strikes an object.