At the February 1982 Ironman World Championship, Julie Moss had a comfortable lead with less than 2 miles remaining. Then her body began to shut down. Staggering and crawling, she dragged herself across the finish line, and into endurance sports lore. The broadcast of Moss’ determination on ABC’s Wide World of Sports has motivated thousands of athletes and helped catapult the fledgling Ironman organization into the giant it is today.

Seeing the broadcast as a 9-year-old, I was conflicted on how to identify the hero. Surely, I admired the grit displayed by Moss. But even as a child I had greater awe for the woman who passed Moss just yards from the finish line for the win: Kathleen McCartney. Despite the heroics, Moss’ pace that day was inconsistent with her fitness, training, nutrition and course conditions. For nearly 2 decades as a coach I’ve asked myself, “Is my coaching developing a Julie Moss or a Kathleen McCartney?” The goal has always been the latter.

I’ve met Julie several times. She’s lovely. The perfect ambassador for the sport. In my profession any hint of criticism of Moss is tantamount to heresy, and I hope my remarks are taken at face value. The events of February 1982 were somewhat of a pyrrhic victory for Ironman and endurance sports. While it provided a needed boost to triathlon, it cemented a perception of mental toughness as primary for many endurance athletes that may take decades to dislodge. Not suffering? Then you’re not trying.

Before the reader pulls a hamstring in rebuttal, let me clarify two points. First, mental toughness is an important component of an endurance athlete’s success, it’s just not foundational. Second, it’s important to distinguish and define (at least for the purposes of this article) mental toughness as the ability to push through physical challenges previously unencountered, from mental fitness as exercise capacity limited and regulated by the brain. Mental toughness is required when faced with a challenge beyond an individual’s physical capacity. Mental fitness is foundational and is elevated with physical fitness through training.

When distinguished from mental fitness, here’s the problem with mental toughness: If you’ve trained properly, you don’t need it. If you need it, you’ve not trained properly. Too many athletes rely on mental toughness as a replacement for physical fitness, while the best athletes do all they can to avoid the need to call on mental toughness. To a professional endurance athlete, mental toughness is like fire insurance. By all means have it, but pray you take precautions so you never need it.

Granted, for some athletes the point is to be a Julie Moss. They enter the sport to challenge and display their mental toughness. Finishing a race feeling strong and looking rested would be a disappointment and a blemish to their image. That’s an acceptable motive, but only if the decision to rely on mental toughness over physical fitness is understood and consciously made.

I had the privilege of coaching James Lawrence, the Iron Cowboy, to his world record 50 Ironman in 50 days in 50 states. Much has been made about James’ extraordinary mental toughness, which is absolutely true. However, of all the 50 days, his fastest Ironman was on day 50 and he crossed the finish line with a smile. How much mental toughness did he need on day 50? Zero. He may have not made it to day 10 without mental toughness, but he never would have made it to day 50 without his inhuman physical fitness. James’ discipline, planning, and proper training was the foundation for the 50-50-50, mental toughness was just another tool at his disposal.

Whether you choose to be a Moss or a McCartney/Lawrence is up to you. My advice is to admire the athletes who suffer. Just emulate the athletes who don’t.