Muscles trained: Quadriceps, hamstrings, glutes

Set up the same way you would for the squat, except when you walk the weight back, take a slightly wider stance and turn your toes out to the sides. Then simply descend to a parallel position, making sure that your knees line up over your toes throughout the movement. Pause when you hit parallel and then press back up to the starting position.

Muscles trained: Quadriceps, hamstrings, glutes

Set a loaded barbell on the supports of a rack or cage just below shoulder height. Step underneath the bar and rest it across your upper trapezius and grab it just outside your shoulders. Lift the bar off the supports and take a step back, positioning your feet so that one is a full 2-3 feet in front of the other. With only the ball of your back foot in contact with the ground, keep your back straight and bend both knees until your back knee almost touches the floor and your front leg forms a 90-degree angle. Pause for a second, then press back up to the starting position.

Muscles trained: Quadriceps, hamstrings, glutes

You can perform any type of lunge with a challenging weight by simply setting it on the supports of a rack or cage and stepping underneath it to load the barbell onto your upper back.

Muscles trained: Quadriceps, hamstrings, glutes

Set a loaded barbell on the supports of a rack or cage just below shoulder height. Next, grab the bar with a shoulder-width grip and step under it, this time resting the weight across the front of your shoulders instead of your upper back. To do this, you'll need good wrist and shoulder flexibility, as you'll bring your elbows underneath the bar and forward so that the backs of your arms are parallel to the floor. Once you've got the bar supported, step back and set your feet shoulder-width apart, eyes focused straight ahead. Keep a natural arch in your back until your thighs are parallel to the floor. Pause for a second, then press back up to the starting position.

Muscles trained: Quadriceps, hamstrings, glutes

Position a bench at the back of a squat rack or cage a full stride behind you. Set a loaded barbell on the supports of a rack or cage just below shoulder height. Step underneath the bar, rest it across your upper trapezius, and grab it just outside your shoulders. Lift the bar off the supports and take a step back as you set your feet shoulder-width apart. Keep one leg in place as you reach the other back and rest your instep on the bench. Keeping your back as straight as possible, bend both knees as you descend until your back knee almost touches the floor and your front knee forms a 90-degree angle. Pause for a second and then press back up to the starting position.

Muscles trained: Quadriceps, hamstrings, glutes

Position a set of 25-pound plates on the floor a foot behind the supports of a rack or cage. Step around a barbell set just below waist level so that it's behind you. Grab the bar with a pronate, shoulder-width grip and lift the weight off the supports. Slowly step back and place your heels on the plates with the balls of your feet in contact with the floor. Keep your torso as erect as possible until you descend to the parallel position. Pause for a second before pressing back up to the starting position.