Fitness influencer Mara Flávia has died while competing in the Ironman Texas triathlon. She was 38. "We are saddened to confirm the death of a race participant during the swim portion of today's Ironman Texas triathlon," Ironman Texas confirmed in a statement shared via Facebook on Saturday, April 18. "We send our deepest sympathies to the family...and will offer them our support as they go through this very difficult time. Our gratitude goes out to the first responders for their assistance.