PURPOSE: To easily change the tension of gut by forming a frame having an outer peripheral recessed part, hermetically closing the outer peripheral aperture in an arbitrary range thereof with a tire, winding the gut on the outer peripheral part thereof to extend the gut and controlling the feed and discharge of air to and from the tire.

CONSTITUTION: This racket has the frame 1 having the outer peripheral recessed part and an inner moving body is put into the frame 1 at need. The V-shaped tire 12 is so disposed as to hermetically close the aperture in the outer peripheral recessed part of the frame 1 to assure the hermeticity over the entire part of the racket frame. The gut is wound around the outer peripheries of the tire 12 and the frame 1 to be stretched. Air is thereafter force-feeded into the tire 12 by operating a manual hammer pump built in a grip end at need to expand and inflate the tire 12 radially outward to increase the gut tension.