Bar Over Mid-Foot
To perform your best squat and deadlift, the bar must be placed over your mid-foot. Period. When it's too far forward, your weight goes toward your toes and you move forward. When it's back too far, your weight shifts away from mid-line and your torso leans toward the rear and becomes too upright. Either too far forward or too far back will result in diminished strength and a less-than-optimal lift. When the bar is directly over your mid-foot, balance is best maintained while force is maximally transferred. If you start the lift ahead of or behind this position, you must expend more energy than necessary to correct the position and get into proper placement. (Your chance of injury also increases when the bar is out of placement.) So be certain to start the lift -- decent for squat and ascent for deadlift -- with the bar directly over your mid-foot; and try to maintain this position throughout the exercise. By doing so, your chance to perform your best lift is ideal.
Foot Placement on the Squat
In order to optimally squat, we must make sure our feet are anchored to the ground correctly. When setting up this exercise, our feet should be approximately shoulder-width apart, with our toes pointed out at roughly 15-30 degrees. (Anatomical structure, mobility, and lift variation -- high-bar, low-bar, and front squat -- will largely dictate the angle of the toes.) By pointing the toes outward, we are creating a slightly wider base, while also allowing for greater external hip rotation. This lets up get back and sit down more easily; it can also activate our groin muscles -- the adductors -- more, aiding in the force placed through the floor. In addition to depth and added force, setting up for the squat in the manner listed helps with knee placement and movement, or lack-thereof. (We don't want the knees to buckle in! We want them shifted outward, like the toes.) Again, foot placement it relative to the individual, with several variables dictating optimal position. If you're able to safely execute the exercise with "your" position, great!
