Up onto the box, then sink back into deep range.
Control the way down into the deficit, don't just drop, that bottom range is the whole point.
Chaining a step-up into a reverse lunge that drops below the box keeps one leg under tension through an enormous range, from full hip and knee extension on top to a deep stretch beneath platform height. The quads own that long range while the glutes control the descent and power both climbs. It suits lifters chasing single-leg strength and deep-range control who have outgrown standard step-ups and lunges.
Depth. Lunging down past the level of the box takes your front leg through more knee and hip bend than a floor lunge allows, and that extra stretched range is where a lot of growth lives. Earn it with control, not by dropping into it.
Lower than a normal step-up box. You have to lunge down past it with control, so start around mid-shin height and only raise it once the bottom position feels smooth and balanced.
You are rushing the transition. Pause fully stood up on the box before stepping back, and place the back foot deliberately. Speed comes after the pattern is grooved.
