After weighing in at an all-time high of 489 pounds, Texas businessman Marcus Cook decided he needed to make a change. After undergoing bypass surgery and committing to a healthy diet and workout routine, Cook dropped an impressive 256 pounds. Not only did he finish the Houston Chevron Marathon, but Cook heard Mike Reilly say, "You are an IRONMAN," as he finished the 2017 IRONMAN Texas triathlon with a time of 16:31:59.