A lightweight play or training device includes an inflatable bladder and a two-piece molded polymer cover formed by first and second closed-cell foam half-shells fused together (e.g., by ultrasonic welding) along a continuous peripheral seam. The bladder, when unconstrained, is significantly larger than the internal volume of the molded cover so that upon inflation it bunches against the inner surface of the cover, thereby absorbing impact energy and slowing aerodynamic flight. Preferred foams have densities of 20 kg m.sup.3 to 60 kg m.sup.3 and Shore A hardness of 30-60. The device may include an integral inflation tube acting as a one-way valve and an optional elastic tether for solo skills practice. Variants include spherical balls and flying discs, as well as alternative seam geometries and joining techniques.

A sports training device (10) comprising a ball (12) with a rotatable coupling (20) located inside the ball (12) that is configured to rotatably connect the ball (12) to a tether (14), such that, in use, the ball (12) is permitted to rotate relative to the tether (14).