Just like building a house, when it comes to shaping your body, you’ll want to forge a strong foundation first. And there’s no better brick than a classic move, to help fortify your muscles and your technique for any other exercises to come.

Once you master the classics, you’ll be able to mix and match them along with their variations, for better workouts and a stronger you. Here’s how to do a perfect lunge.

The lunge is like the one-trick pony of fitness: You can do it anywhere, use it to build foundational strength, add to it for compound (full-body) exercises, and even perform it as a walking movement, to create a dynamic (active) warm-up stretch. This pony is also an excellent calorie-burning move, as it challenges large muscle groups, like your thighs and glutes—all at once. Insider tip: Lunges are one of the best ways to give your booty a visible lift.

Stand, and with your chest up and eyes ahead, step two to three feet forward with your right foot. Allow both knees to bend until your front knee is at about a 90-degree angle, with your knee behind your toes, and your back knee a few inches above the floor. Press into your right foot, and press back to start. Repeat, stepping forward with your left foot, and alternate legs for 8 to 12 reps per side.

Creating compound moves allows you to work several muscles at once to form a total-body exercise. You also challenge yourself with different movement patterns, which helps to hone your balance, coordination, and general athleticism—all of which can help prevent injuries. This move tones your thighs, glutes, arms, and shoulders.

Stand with two lightweight dumbbells (about two to five pounds, each), held at chest height, palms facing forward. Step forward into a lunge, and as you lower your body toward the floor, press the dumbbells overhead, keeping your elbows slightly bent, and arms just in front of your ears. Step back to start, and lower the dumbbells, repeating on the other side. Alternate for 10 to 20 total reps.

As its name suggests, this move helps fine-tune your balance, and provides an extra challenge to glutes and thighs. Balance lunges also work your core, which fires up to help stabilize your body during the entire exercise.

Stand two to three feet in front of a bench or sturdy chair, and place the top of your left foot on the bench. Slowly lower into a lunge, keeping your right knee behind your right toes. Press back up to start, and perform 8 to 12 reps before switching sides.

This lunge not only delivers an extra balance and core challenge, but it’s fun. It also forces you to land softly and slowly on your back leg, creating an added strength boost.

Stand with your hands on your hips, clasped in front of your chest, or holding a light pair of dumbbells, and step forward with your right foot, into a lunge. Press your body up toward your start position, and kick up with your left leg before stepping your left foot back behind you into a lunge. Perform 8 to 12 reps before switching sides.

Lunges don’t have to simply move in one direction. This version works your body laterally, challenging the sides of your thighs and glutes—areas you may not ordinarily train. Performing side lunges not only works your lower half a little harder, but helps to prevent injuries, by strengthening your muscles in new ways.

Stand with feet hip-distance apart, with your hands clasped at your chest or on your hips, and your hips and knees slightly bent. Keeping your chest and head up, step about three feet to the side with your right foot, with your toes facing forward, and maintaining your slightly lower stance, bend your right knee and sink your hips low toward the floor. Press back off your right foot and return to start.