Going from Western Kanssas to Centennial in Denver, 7A, moderate turbulence, and able to handle the bumps. Twenty miles from Denver, I guess I hit an air pocket or a huge gust. My head hit the canopy, everything in the plane was thrown everywhere, And Ibumped my leg against the bottom of the panel. Lost about seven humdred feet and bank angle went to about 45 degrees. Pulled the power back gained control and climbed back to altitude. This all happened in about 10 seconds. Now I believe in the 5 point belt system and will always be wearing my crotch strap.