the pant is too restrictive for badminton. oxymoron theme here, sleeveless shirt for better cooling and less restriction but lengthened short for the oppositive effect http://www.badmintonforum.com/vb/showthread.php?t=21071&highlight=silver sleeveless shirt done in badminton already.
Interesting, in the beginning, tennis player wear long pants, then changed to shorts, then kept getting longer and longer. Similiar to basketball. That make the badminton shorts look very old fashion. A while back, I saw Sun Jun wearing pants to his knees while practising. It looked quite good.
have not seen the real thing but believe the pants is stretchable http://www.tennis-warehouse.com/descpageMANIKE-NMDFC.html