Knees caving in coming out of the bottom of the squat

[Marco Silva]

Hello!

I’d like some help for my wife please. She is having a problem with her squat. Her knees are caving in coming out of the bottom of the squat. It only happens when the weight gets heavy for her. She’s in her early 30’s, 5’3 about 140lbs. She’s nearing the end of her LP squatting 170 for 5 sets of 3.

How can she improve this problem?

Thank you!

[Mark Rippetoe]

Did her knees cave at 160 x 3 x 5?