Intense interval training for short periods of time may make you fit, but apparently not slim.
http://topix.net/r/0a0H2TVFa7i=2FqwY3EVp2ljywWKTrKVuWqj4jlMfGc612R6a4EUrlSB9SJNOBaBcHtZ8SCa30=2FypiyS=2FekUPWJFQ61pBHABTmaqbkVLwxp4=2Fc=3D
http://topix.net/r/0a0H2TVFa7i=2FqwY3EVp2ljywWKTrKVuWqj4jlMfGc612R6a4EUrlSB9SJNOBaBcHtZ8SCa30=2FypiyS=2FekUPWJFQ61pBHABTmaqbkVLwxp4=2Fc=3D