As you already know, the barbell back squat is No. 1 on our list. But the exercise ranked runner-up is a close second in the eyes of many, especially those who like the idea of big, beefy quadriceps and the more direct line of resistance offered by moving the barbell to the front versus draping it across the upper back.
Main Areas Targeted: Emphasis on quads, plus glutes, hamstrings, calves and core
Strengths: Both the barbell front and back squats are great exercises for increasing leg, back and core strength and for positively affecting anabolic metabolism. As for which is better, it depends on your posture, technique, previous injuries and personal preference. For example, if you lack proper shoulder external-rotation capability, then back squats might not be your best option. Due to your poor shoulder and thoracic spine mobility, you may have issues getting the bar racked and properly positioned across your back. In that case, front squats would quite possibly be a much better choice.
How-To: Set the pegs in a power rack just at or below mid-chest, and place the safety bars at a level between your hips and knees. Step up to the bar, crossing your arms to build a shelf to cradle it at your front delts and upper chest. Keep your chest up, lower back and abs tight, and eyes forward as you step back into a shoulder-width stance. Bend your knees and hips as if sitting in a chair until your thighs are at least parallel to the floor, then reverse direction by driving through your heels and pressing your hips forward to return to standing. Keep your neck and back straight and elbows lifted high throughout the lift. Inhale to support the trunk and abdomen at the start of your descent, and keep your core and abdomen engaged to help minimize stress on your lower lumbar area.
If you have problems holding the bar in the clean position, try wrapping wrist wraps around the bar and holding onto the wraps. This will help you maintain bar placement.