Herschel Walker Still Does 3,500 Sit-Ups Daily, Offers to Train Trump!
Herschel Walker is 56 years old ... and he's still in INSANE shape -- telling TMZ Sports his daily routine includes 1,500 push-ups and 3,500 sit-ups. THAT'S NOT A MISTAKE -- HE REALLY DOES THAT! The ex-NFL star was leaving the White…