Two words - Mike Mamula
From Wikipedia:
Mamula improved his draft stock tremendously thanks to his showing at the NFL Combine. He was one of the first players to train specifically for the combine drills, performing each drill hundreds of times in the months leading up to the combine. Although that practice is prevalent today, in 1995 most players performed football drills and paid less to attention to the specific drills measured at the combine.[1] Mamula had 28 reps of 225 lb bench presses, which was more reps than the top tackle taken in the draft (Tony Boselli), and his 4.58 40-yard dash time was considered extremely fast for his position.[2] He scored a 49 out of 50 in the Wonderlic Test, which is the second highest score ever recorded by an NFL player.[3] In addition he also had a 38" vertical jump, higher than CB Jimmy Hitchcock.[4]
Don't buy into the workout hype.
Peace