Squats are considered a "functional movement" because we use this type of movement every single day, when we sit & stand or bend & lift. It is important to be able to have comfort and confidence with this lower body move. I hear many people say, "I don't do squats, because they hurt my back." Or, "I don't do squats because they hurt my knees." Proper alignment, will prevent pain, and potential injury. There are 3 typical movement patterns that may occur during a squat:
1.) Lumbar dominant: This is primarily due to tight hip flexors. The gluten and abdominals do not contribute enough support and strength. The hip flexors pull the pelvis forward, causing the back to do most of the work.
2.) Quadricep dominant: This is primarily due to loading the quadriceps and allowing sheer force on the tibia as the femur moves forward. Once in the lowered position, the gluteus maximus does not properly "load" and generate adequate force moving into the upward phase.
3.) Glute dominant: The glute dominant squat is the preferred pattern, as it relieves "strain and pain" on the lumbar spine and knees. The movement is initiated by pushing the hips back, as if sitting into a chair. This maximizes the load on the gluteal muscles during the downward phase, and prepares the body to generate adequate safe force in the upward phase.
It is important not to load the muscles with additional weight, until you can properly execute the squat movement with proper form and alignment. Your body weight and gravity (nature's force and resistance), are very effective for results in squats and lunges. Be honest with your ability to maintain alignment, as you perform this highly valuable functional movement.