5 sets
Set 1 15 reps medium weight
Set 2 12 heavier reps with 2 second slow count on descend
Set 3 10 heavier reps with 2 second slow count on descend
Set 4 8 heavier reps with 2 second slow count on descend
Set 5 8 heavy reps with 2 second slow count on descend

Notes: Increase weight each set and go slightly heavier than your usual at least 5-10 pounds heavier in your last set, keep the bar close to your shins as you move up and down to avoid back pain or injury, pay attention to back form in video, rest 90 seconds between sets.