Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
It is safest to perform the lunge inside a squat rack. Set up for the exercise by setting the barbell to just below shoulder height and loading the weight you want to use. Stand under the bar with your feet at about shoulder width apart. Position the bar so that it is resting on the muscles on the top of your back, not on the back of your neck. The bar should feel comfortable. If it doesn't, try adding some padding to the bar. Now take your hands over the back and grip the bar with a wide grip for stability. You should now bend at the knees and straighten your back in preparation to take the weight off the rack. Keeping your back straight and eyes up, push up through the legs and take the weight off the rack. Take a few steps back and stabilize yourself. You are now in the starting position. Step forward with your left leg while maintaining your balance and squat down through your hips. Keep your torso straight and head up. Don't allow your knee to track out over your toes. Push yourself back to the starting position by using your heal to drive you. Repeat this movement with your right leg and then repeat for desired reps.
Never allow your knees to track out over your toes during this movement. Doing so will place undue stress on the knee joints. This exercise requires a good deal of balance and is not recommended for those with balance issues. Begin by using a very light weight to first perfect the movement. Keep your head up and back straight throughout the exercise. Never allow your back to round.
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