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Some exercises never go out of style, but a few great moves unfairly fall out of fashion. Below are four classic leg movements that not many remember, but everyone should be doing. There's a reason they've been working for people for decades, even if they've disappeared from gyms. These four moves, drawn from both athletics and weightlifting, boost power, increase strength, and will upgrade your next leg day.

Cossack Squat
Do this move at the start of a strength workout as a dynamic warm-up to loosen tight hips and strengthen weak adductors (inner thighs) through a full range of motion. Stand with your feet at about twice shoulder-width apart and turn your toes out slightly. 

Squat as deep as possible on the left side, your weight should be on your left heel. To maintain balance, extend your arms straight out in front of your body. Keep your right leg straight and flex your right ankle, pulling your toes up toward the ceiling. Pause, return to the start and repeat on the opposite side. That's one rep. Perform 15 reps, then rest for 45 seconds. Complete two sets. If you need help balancing, hold onto a wall or bench for support. You can also start with a shorter range of motion to accommodate tight hips.

Resistance Band Sprint
Unlike barbells and dumbbells, elastic bands create constant tension throughout the movement to recruit more muscles. Better still, sprints boost explosiveness in your thighs, particularly the hamstrings. Loop a large band around a sturdy anchor (like a squat rack) and place the other end around your waist. Walk away from the anchor point until there is a slight tension on the band. 

Explode straight ahead to sprint for two to three full strides, touch the floor, and then slowly walk backwards to the start. Complete three sprints, rest for 60 seconds, and then repeat for three total sets.

Barbell Single-Leg Romanian Deadlift
This deadlift variation doubles as a core exercise because your abs and lower back work overtime to stabilize your body. Grab a barbell with an overhand grip, slightly wider than shoulder width. From standing, keep your arms straight, push your chest out, tense your abdomen (like you're bracing for a gut punch), and hold the bar in front of your hips. Set your feet hip-width apart with a gentle bend at your knees. Place your right foot behind you and balance on your left. 

Without moving your knees, or rounding your back, hinge at your hips and lower your torso until it's about parallel to the floor. Pause, clench your glutes, drive your hips forward, and return to the start. Complete five reps with the same leg, then do five more on your other leg. Pick a weight that allows you to perform near-perfect reps. Rest for 45 seconds and do two sets.

Barbell Walking Lunge
Skip your long, slow cardio routine and replace it with this short-burst conditioning drill. Grab a barbell and hold it across your upper back with an overhand grip. Stand with your feet shoulder-width apart, shoulders pulled back. Brace your core and maintain a natural arch in your lower back. 

Step forward with your right leg and lower your body until your forward knee is bent to 90 degrees. Pause, then stand straight up and bring your back foot forward. Repeat with the opposite leg to lunge walk across the floor. Complete 20 reps per leg (40 total reps). Beginners should start with an empty 45-pound bar with the goal of working up to 25-pound plates. Advanced lifters can start with 45s. If you can't maintain perfect form, drop down in weight to avoid injury. If you don't have much space to move around, lunge standing in place.