Fitness star Hayley McNeff died on Friday, August 8. She was 37. "Such a bright light has left this world too soon with the unexpected but peaceful passing of Hayley C. McNeff on August 8, 2025," an obituary published by Boston.com on Tuesday, August 12, read. McNeff, who amassed more than 2,000 followers on Instagram, was born and raised in Concord, Massachusetts. She graduated from Concord-Carlisle High School and the University of Massachusetts Amherst with a Bachelor of Arts degree, according to the obituary.