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Beginning (gram on left) – Using no weights, step back to a lunge, then stand with your feet together, then step forward to a lunge.

Intermediate (mom in middle) – Using light/medium weights, step back to a lunge, then stand with your feet together, then step forward to a lunge.

Advanced (me on right) – Using a heavy dumbbell, step forward and back to lunges without stopping in the middle.