This isn't a kb/db complex, but I just tried a Ross Enamait (tm) medicine ball interval thingie today, and it was exhausting! All it was was 8 rounds (no rest) of 10 medicine ball choppers, 15 slams and 10 burpees. And I was only using an 8 lb ball! I didn't realize how wiped I was until I attempted to run back to work afterwards.
