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Late last month, a 43-year-old New York-based banking executive, Slava Leykind, fell ill while attempting the “Everesting” challenge at Snow King Mountain in Jackson Hole, Wyoming. This trend—which has grown in popularity with uphill athletes around the world—involves picking a hill and riding, running, or skiing up and down it (often, with no sleep) until you climb 29,032 feet, the height of the tallest mountain in the world.
Hikers don’t need to enroll in a formal “Everesting” event to participate in the challenge, but several peaks around the world hold competitions. Some athletes opt to tackle half or a quarter of the elevation gain of Mt. Everest as an alternative. Some formal competitions like the one in Jackson Hole come with an entry fee of up to $6,000. This is the third year that Jackson Hole hosted the “Everesting” challenge, and it had about 300 registered participants. Snow King Mountain is among the steepest peaks that athletes tackle in an attempt to climb 29,032 feet.
Leykind successfully tackled Snow King Mountain six times, climbing 9,426 feet, before falling ill. Five days later, Leykind died due to “an electrolyte imbalance causing cardiac arrest,” according to the Teton County coroner.
Although it’s unclear what type of electrolyte imbalance Levykind experienced, the most common type amongst endurance athletes is hyponatremia, which can happen when athletes drink too much water without replenishing sodium levels. In acute hyponatremia, low sodium can cause brain swelling, a coma, and death.
Complications from hyponatremia have led to at least 14 athlete related deaths in the past 44 years. In events like the one that Leykind was participating in, medical professionals are typically nearby to treat conditions like hyponatremia. Leykind’s family is currently investigating the treatment he received prior to his death.
The Mayo Clinic advises athletes to educate themselves, to drink sports beverages during demanding activities, and to drink the appropriate amount of water during endurance sports to avoid hyponatremia.
Leykind achieved early success in his field. His obituary read: “Despite his significant professional success at a young age, Slava’s role as a husband and father was his greatest achievement, passion and pride. He fervently supported his children, bringing love and a sense of calm to the wonderful chaos of a full house.”
From 2025