BANGKOK — In the ring, the two boxers spar furiously with blows delivered by fists, elbows, knees and feet to virtually any part of the opponent’s body. Those in the crowd furiously make wagers with each other as the battle rages. The Muay Thai — or Thai kickboxing — competitors are as young as 8 years old. But the tragic death of 13-year-old Anucha Tasako after being knocked out in a match earlier this month has brought into focus whether youngsters should be taking and giving such brutal punishment in the name of sports. Anucha, who fought an incredible 174 bouts in a career that started at age 8, died of a brain hemorrhage two days after his Nov.