Weighted Sissy Squat

How to do it

Standing upright, with feet at shoulder width and toes raised, use one hand to hold onto the beams of a squat rack and the opposite arm to hold a plate on top of your chest. This is your starting position.
As you use one arm to hold yourself, bend at the knees and slowly lower your torso toward the ground by bringing your pelvis and knees forward. Inhale as you go down and stop when your upper and lower legs almost create a 90-degree angle. Hold the stretch position for a second.
After your one second hold, use your thigh muscles to bring your torso back up to the starting position. Exhale as you move up.
Repeat for the recommended amount of times.

What muscles does the Weighted Sissy Squat work?: Mainly the quads, with help from the calves, glutes, hamstrings.
What equipment do I need?: Barbell.
Is it good for beginners?: It is rated expert level, so learn simpler versions first.
How do I track progress on it?: Log each set and beat the weight or reps from last time. Liftrung shows your last set beside the next one and estimates your one-rep max from your sets.

Exercise descriptions: free-exercise-db, public domain.