It's a Catch 22 for women. We need to be active for good health, but at the same time we're up to eight times more likely than men to suffer an Anterior Cruciate Ligament injury. Doctors aren't sure about the reasons why, but they do have some preventive medicine in July's Health Check report.

If practice makes perfect, Christy Estlund is a knee injury expert.

"It just gave out and I heard a big pop," she said.

After tearing her ACL playing college soccer and again several years later, she felt the same pain a month ago while playing with her children.

Dr. Sean Mullendore with Alegent Health confirmed her fear.

"I think she torn her ACL again," he said.

Christy tells us, "It's more difficult as you get older, have a family, and kids and your body doesn't heal as well."

Doctors don't know why women are more prone to the injuries. It could be a matter of flexibility, strength, or alignment but certain sports do put women more at risk -- especially the quick stops and starts of basketball, soccer, and volleyball.

Dr. Mullendore says, "One bit of advice I give young women is to try and vary their activities a little bit. Don't play one sport year-round. If they cross train, soccer one time of the year, basketball another, they're less likely to put the same strain on muscles, ligaments, and tissues."

Even low impact activities like biking and swimming will have to be cut back for Christy Estlund. She'll endure a third surgery and almost a year of rehabilitation to be able to play with her kids.

"In the end it's well worth it," she says. "You can be strong and you will get through it. It's very emotional. It's not easy but there is hope in the end."

One of the best things patients can do after healing from ACL surgery is to stay active. It reduces the risk of arthritis, as does maintaining the proper weight.