There are a few different machines in the gym for this- you can do them seated like me, or lying! If seated, place your ankles on top of the padded bar. Engage your core, and use your hamstrings to press down on the bar & think about curling it down underneath you. Use the resistance of the weight on the way back to starting position too.

Weight Reccomendations:
Beginner:14-40lbs
Intermediate:45-80lbs
Advanced:85-100lbs

*Modification: you can do these lying with medicine ball or band!