Marathon runner, 24, texted her father 'Ow, ow' before she collapsed and died of a rare muscle condition

Rachel Apa, 24, a former field hockey player at Bucknell University, collapsed at mile 24 of the New York City Marathon on Sunday — her first race, which she had entered to raise funds for Parkinson's research in honour of her late grandfather. Her father Steve, tracking her from Pennsylvania via a location app, noticed her marker had stopped moving after her texts went silent; her mother Michelle had watched her smiling and high-fiving the crowd at mile 14 before heading to the finish line to wait for a daughter who never arrived.

Rhabdomyolysis, the condition that killed Rachel, occurs when muscle fibres break down and release toxic proteins into the bloodstream, and can strike even athletes who are physically fit and healthy.

While bystanders took turns performing CPR, one person remained beside Rachel holding her hand until paramedics arrived; she was rushed to hospital but could not be saved.

Survivor Madina Alam, 34, who developed the same condition after a pull-up session, said her arms swelled by 12 pounds — a warning of how rapidly rhabdo can escalate.