Abstract: A skate assembly having front and rear attachment portions adapted to be incorporated into or attached respectively to the sole and heel of a boot; and an elongate sub-assembly including a molded polymeric frame having a lower portion in which an ice blade or wheel are mounted and spaced front and rear upper portions each having spaced side wall portions projecting from the lower portion. The upper portions can be releasably attached to the attachment portions by engaging longitudinal tongues on one of the portions in grooves in the other, and a fastening system is provided for retaining the portions with the tongues in the grooves in an engaged position.