Hip position and bar position during the movement. During the RDL the hips will drive backward during decent and the bar will glide along closer to the body. With a SLDL, your hips almost stay put and the bar is extended further out from the body, thus placing more stress on the hams and lumbars. Of course during both movements, the knees are always slightly bent. I don't know why they call them "stiff legged" when the knees are bent? It's hard to explain in writing but I hope you get the drift?
Yes I get what your saying. I thought the same thing you just said but just wanted 2nd opinion because watching viids there really no diff.
RDL you dont touch the ground
Serious Nutrition Solutions
when i do stiff legs, i end up with 3 or 4 light sets while standing on a riser, lowering the bar to touch my toes, and keeping my legs as straight as possible. i lift through my heels, and squeeze it out at top, then return to get a good stretch.
when i do romanians, i start the set with a deep hip stretch at the bar, take the weight as if a deadlift, and with subsequent reps focus on replicating basically the last 80% of a deadlift, keeping the legs only slightly bent.
i tend to do these on the same day, romanians first and heavier, in place of squats, and coupled with extensions...