Provided are tubular carbon fiber reinforced composite material and having excellent cylindrical bending strength and a golf club shaft using the same. This tubular carbon fiber reinforced composite material is formed by laminating and curing a straight layer and a bias layer. The straight layer comprises carbon fibers S coated with a sizing agent S and arranged in parallel in a direction of −20° to +20° with respect to the axis of the tubular body, and contains a thermosetting resin S. The bias layer comprises carbon fibers B coated with a sizing agent B and arranged in parallel in a direction of +25° to +65° with respect to the axis of the tubular body, and contains a thermosetting resin B. The carbon fiber reinforced composite material constituting the bias layer has an interlaminar shear strength of not less than 110 MPa. A cured product of the thermosetting resin S has an elastic modulus of not less than 4.0 GPa.

Provided are tubular carbon fiber reinforced composite material and having excellent cylindrical bending strength and a golf club shaft using the same. This tubular carbon fiber reinforced composite material is formed by laminating and curing a straight layer and a bias layer. The straight layer comprises carbon fibers S coated with a sizing agent S and arranged in parallel in a direction of −20° to +20° with respect to the axis of the tubular body, and contains a thermosetting resin S. The bias layer comprises carbon fibers B coated with a sizing agent B and arranged in parallel in a direction of +25° to +65° with respect to the axis of the tubular body, and contains a thermosetting resin B. The carbon fiber reinforced composite material constituting the bias layer has an interlaminar shear strength of not less than 110 MPa. A cured product of the thermosetting resin S has an elastic modulus of not less than 4.0 GPa.

An active suspension orthotic support system is disclosed. The suspension orthotic support system comprises at least one variable resistance beam extending from a heel section to a mid-arch section of the footwear, wherein rotation of the variable resistance beam from a first position to a second position causes a resistance provided by the variable resistance beam to vary between a minimum resistance to a maximum resistance.

An active suspension orthotic support system is disclosed. The suspension orthotic support system comprises at least one variable resistance beam extending from a heel section to a mid-arch section of the footwear, wherein rotation of the variable resistance beam from a first position to a second position causes a resistance provided by the variable resistance beam to vary between a minimum resistance to a maximum resistance.

A golf tip plug housing includes an exterior surface configured to be securably affixed to a butt end of a golf club shaft and an interior surface configured to securably receive a golf tip plug having an outer diameter of either: (a) 7.0 mm-7.6 mm or (b) 4.0 mm-4.6 mm. In one aspect, a golf club includes a head and a shaft having a tip end attached to the head and a butt end opposite the tip end. A tip plug includes a stem and a head. The tip plug stem has an outer diameter sized to be insertable in the tip end. A tip plug housing has an outer diameter sized to be insertable in the butt end and an inner diameter sized to receive the tip plug. The tip plug is positioned in the tip plug housing and the tip plug housing is positioned in the butt end.

A golf club has a first shaft coupled to a club head, a second shaft configured to slidably engage a portion of the first shaft, a grip coupled to the second shaft, and an adjustable length shaft assembly received by the second shaft and configured to allow a portion of the first shaft to slide in relation to the second shaft in a first configuration, and to restrict a portion of the first shaft from sliding in relation to the second shaft in a second configuration. The grip is restricted from rotation about the first shaft or the second shaft as the first shaft slides in relation to the second shaft.

Various embodiments of a two-piece golf shaft are provided, which include a hollow upper section, a hollow or solid lower section formed from an injection-molded chopped carbon fiber/thermoplastic material, and a coupling insert configured to join the lower section to the upper section (and, optionally, to the golf club head as well).

Various embodiments of a two-piece golf shaft are provided, which include a hollow upper section, a hollow or solid lower section formed from an injection-molded chopped carbon fiber/thermoplastic material, and a coupling insert configured to join the lower section to the upper section (and, optionally, to the golf club head as well).

The present disclosure relates to a shaft for athletic activities comprising, along at least a part of the length of the shaft: an internal wall (31) made of a first fiber-reinforced composite; and an external wall (30), fixed to the internal wall, and made of a second fiber-reinforced composite, wherein one or more cavities (32A, 32B, 32C) are present between the internal wall and the external wall.

The present disclosure relates to a shaft for athletic activities comprising, along at least a part of the length of the shaft: an internal wall (31) made of a first fiber-reinforced composite; and an external wall (30), fixed to the internal wall, and made of a second fiber-reinforced composite, wherein one or more cavities (32A, 32B, 32C) are present between the internal wall and the external wall.