The hack squat machine primarily targets the quadriceps, which are the muscles in the front of your thighs. However, it doesn’t stop there. Hack squats also engage the hamstrings, glutes, and calves to varying degrees. This comprehensive lower body engagement means you can develop strength and definition in multiple muscle groups with a single exercise.

This exercise involves standing with an exercise ball between your back and a wall, then squatting down while keeping your back against the ball. It helps to strengthen the legs, glutes, and core muscles.

12 Goblet Squats
60 second Wall Sit
12 Barbell Squat
20 Calf Raises
25 leg Extensions
24 Walking Lunges

The step up is a lower body compound exercise that involves stepping up onto an elevated surface such as a step or box. Step ups work the glutes, quads, hamstrings, adductors and abductors, calves, and core, and can help to improve stability and reduce muscle imbalances between the two legs.

A static lunge is a great place to start to understand the proper form of a lunge. During this exercise, your feet don’t move; they stay in the same spot until you switch legs entirely.

To do the Squat to Lunge, start with your feet about hip-width to shoulder-width apart. Squat down, sitting your butt back. Do not round forward as you squat down. Keep your heels down and sink your butt so that your quads are about parallel to the ground.
Then jump up and switch into a lunge stance as you land. One foot will be forward and then other will lunge back as you drop your back knee down toward the ground. Sink low in the low and keep your chest up.
In the lunge, your front heel should be down and your weight should be fairly centered.
Jump back into the squat and then lunge on the other side. Move quickly, exploding up off the ground to switch.
Beginners can start with stepping between the two moves instead of jumping.

This is just horrid but amazing.
45 second hold on a Leg Extension either full contraction (top of range) or full extension (weight off the stack but only just). Then 10-12 reps. Once done, 30 Walking Lunges