A swim training aid apparatus is provided for use on a limb of a swimmer, during a swimming motion. The training aid includes a flexible band member configured to extend circumferentially around the limb, and a lock device cooperating with the band member to releasably retain the same around the swimmer's limb. The training aid further includes a substantially non-absorbent, flexible material sheath having one end thereof mounted to the band member, and an opposite end thereof extending distally past and terminating beyond the limb.