I am on Waterbury’s Quattro Dynamo program, and it calls for legs curls. Well the leg curl machine at my gym… is broken. They only have one. Anyone have any suggestions on what I should do to replace that exercise?
You should be able to substitute with one of these:
Glute ham raises
Stiff-legged deadlifts (barbell or dumbbell)
Give one of them a try!
Nate gave you some great exercises, the only thing I would add would be band leg curls if you have a band.
If you want more of a semi-isolation movement, somehow attach your ankle to a low-pulley, stand facing the stack, perform a leg curl to just before a 90 degree knee bend. You will have to use your glutes to stabalize. Also, try this from different angles, such as aligning yourself in a fashion (seated) that allows your leg to be parallel to the line of force when its extended. This angle will force you to use your hip flexor to stabalize.