RIO GRANDE CITY – Heart disease is the number one cause of death for women in the United States. It kills 400,000 every year, according to the American Heart Association.

Nelly Lozano is a grandmother and also a 51-year-old CrossFitter who spends her off-time in the gym. She works at the Starr County Courthouse working for the county attorney. She also suffered a mild heart attack.

Many would wonder why someone with a healthy lifestyle would suffer a heart attack. It ends up her symptoms were different, which is often the case with strokes and heart attacks in women.

Lozano mistook a little muscle discomfort for workout soreness. Her family history was also a factor: her mother had a heart attack at the age of 45. However, her mother was a smoker. Lozano doesn’t smoke at all.

Lozano also felt fatigue when she was at work or the gym.

“Sometimes I would be just standing still and it felt like the floor was moving underneath me. It felt awful, but … I said it will go away in a little bit, it's just that I didn't sleep well,” said Lozano.

Nausea and dizziness are symptoms of a heart attack. It’s just less commonly associated than chest pain. This is where gender comes in play.

Watch the video above for the full report.