Former heavyweight boxing champion Riddick Bowe of the U.S., right, gets a kick on the leg by Levgen Golovin of Russia, center, during their World Muay Thai or Kick Boxing Super Heavyweight Championships fight in Pattaya, Thailand, June 14. (AP Photo/Apichart Weerawong) by Joceyn Gecker PATTAYA, Thailand (AP) — Riddick Bowe now understands why people warned him that Muay Thai is a dangerous sport.”I would have to say, they have a valid point,” said Bowe, after his debut in Thai kickboxing ended with a thud in the second round. “It’s much harder than boxing.” The former world heavyweight boxing champion had hoped to prove his critics wrong and show that he could comeback from retirement into an entirely new sport and revive some of his past glory. But Bowe is now 45 and weighs 300 pounds, and he looked it Friday in his first fight since 2008. Slow and out of shape, the fighter known as “Big Daddy” took a big beating from his 30-year-old unheralded Russian opponent Levgen Golovin, who attacked with repeated kicks to the shins that knocked Bowe off his feet five times. The bout ended with a technical knockout after his last fall when Bowe sat on the ground clutching his legs, wincing in pain.