A jump height measuring device with an arrangement of impact elements that are arranged one above the other at a respective distance in a longitudinal direction and which can be pivoted individually transverse to the longitudinal direction, wherein the number of pivoted impact elements forms a measure for a jump height. Each impact element can be pivoted out of a base position against a return force in at least one pivoting direction, up to a defined end position.

A torso protector device for martial arts is disclosed. The device comprises a cylindrical torso protection body to protect a wearer's torso; a shoulder cover coupled to the cylindrical torso protection body at front and rear portions thereof, wherein the shoulder cover has a neck opening defined in a top thereof, wherein left and right arm passing openings are defined in the shoulder cover in the left and right sides thereof respectively; a wire coupled to the cylindrical torso protection body and the shoulder cover; a wire adjuster module coupled to the wire; and a screener to screen the wire, wherein an adjustment dial is operatively coupled to the wire adjuster module, wherein the rotation of the adjustment dial results in length increase or decrease of the wire.

A variable-color region (106) of an information-presentation structure extends to an exposed surface (102) at a surface zone (112), normally appears along it as a principal color, and includes pressure-sensitive color-change structure (132) and pressure-spreading structure (242) having an internal pressure-spreading surface (244). An object (104) impacts the zone at an object-contact area (116). The pressure-spreading structure spreads pressure of the impact along a distributed-pressure area (256) of the pressure-spreading surface. A segment (142) of the pressure-sensitive color-change structure responds to the excess internal pressure along the distributed-pressure area by causing an impact-dependent portion (138) of the variable-color region to temporarily appear along a print area (118) of the zone as changed color materially different from the principal color if the excess internal pressure meets excess internal pressure criteria. The print area thereby closely matches the object-contact area in size, shape, and location.

Principal and secondary regions (106 and 108) of an information-presentation structure extend to an exposed surface (102) respectively at principal and secondary surface zones (112 and 114) variously impacted by a spherical object (104) that rebounds from the surface. The principal region normally appears along the principal zone as a principal color. An impact-dependent portion (138) of the principal region responds to the object impacting the principal zone at an object-contact area (116) by temporarily appearing along a print area (118) of the principal zone as changed color materially different from the principal color. The print area closely matches the object-contact area in size, shape, and location. The secondary region fixedly appears along the secondary zone as a secondary color. Restitution matching is provided across the two zones so that the rebound characteristics of the object are largely independent of whether it contacts the principal or secondary zone.

An apparatus for use in an American football type game includes an elongate structure defining a generally tubular body having a length extending between two opposing ends, a width, and a handgrip portion located between the ends. The width of the tubular body is generally uniform along the entire length of the body. An attachment mechanism removably receives the elongate structure at an attachment point and limits movement of substantially the entire elongate structure to that of the attachment mechanism at the attachment point. The attachment mechanism is configured to release the elongate structure therefrom when a force that overcomes an attachment force provided by the attachment mechanism is applied to the handgrip portion.

A variable-color region (106) of an information-presentation structure extends to an exposed surface (102) at a surface zone (112) and normally appears along it as a principal color. An impact-dependent portion (138) of the variable-color region responds to an object (104) impacting the zone at an object-contact area (116) by providing an impact signal if the impact meets threshold impact criteria. The impact signal identifies an expected location of a print area (118) in the zone. The print area meets one of plural different print-area location criteria respectively corresponding to plural changed colors materially different from the principal color. Responsive to the impact signal, a controller (702) determines which location criterion is met by the print area and provides an initiation signal at a corresponding condition. The impact-dependent portion responds to the initiation signal by temporarily appearing along the print area as the changed color for that location criterion.

An exercise assist tool is used together with an exercise tool used in a supine or seated state, and the exercise assist tool includes a body-axis indicator that allows a user to be conscious of a body axis. The body-axis indicator has a longitudinal direction, and is supported such that the longitudinal direction can be disposed along a craniocaudal axis of the user. The body-axis indicator is a rod member supported so as to be disposed along a craniocaudal axis of the user. The body-axis indicator includes a proximal-side indicator provided in front of a face of the user, and a distal-side indicator provided farther from the user than the proximal-side indicator. The proximal-side indicator is configured to be capable of adjusting a distance from the user.

Disclosed is system and method for measuring the tension of a tennis net, and, alternatively or in addition, for determining if a service let occurs via the measuring of the net tension. The disclosed embodiments measure a force exerted on the center-strap or the singles stick by the net. In these embodiments, the measured force provides an accurate reflection of the tension of the net.

Disclosed is system and method for measuring the tension of a tennis net, and, alternatively or in addition, for determining if a service let occurs via the measuring of the net tension. The disclosed embodiments measure a force exerted on the center-strap or the singles stick by the net. In these embodiments, the measured force provides an accurate reflection of the tension of the net.

Disclosed is system and method for measuring the tension of a tennis net, and, alternatively or in addition, for determining if a service let occurs via the measuring of the net tension. The disclosed embodiments measure a force exerted on the center-strap or the singles stick by the net. In these embodiments, the measured force provides an accurate reflection of the tension of the net.