Set the barbell on the squat rack at chin height. Stand under the bar so it rests comfortably on your shoulders. Place your hands on the bar in an overhand grip (palms away) slightly wider than your shoulders. Stand tall and release the barbell from the squat rack. Take a small step with your feet slightly further than shoulderwidth apart. This is your starting position (A). Inhale. Looking ahead, bend at the hips and knees, keeping your knees in line with your toes, until your thighs are parallel with the floor (B). Ensure your back stays within a 45o to 90o angle to your hips. Exhale as you push through your heels and extend your legs to return to the starting position. Do as many reps as you can in 20 seconds.