“I like to suffer,” says Britain’s Lucy Charles, who has transitioned from ultra-swimming to top performances in triathlon both as an age-grouper and in the past year a pro. Tolerating discomfort has been a trademark of sorts for Charles as she used to swim 60 miles a week in training for her previous sport. At Ironman Lanzarote, her first of 2017, she came within 11 minutes of Paula Newby-Fraser’s 1995 record. Only 24 years old and just beginning to figure out the sport (and have enormous success regardless), keep an eye on Charles on Saturday.