Conventional Deadlift vs. Stiff-Leg Deadlift

The conventional deadlift starts with the hips lower and the knees bent enough to put the shins near vertical over the bar. The pull is initiated with a leg drive — quadriceps and glutes extend the knees and hips simultaneously — and finishes with a hip lockout. Because multiple large muscle groups contribute, conventional deadlifts tolerate the heaviest loading of any pull.

The stiff-leg deadlift starts with the knees nearly straight and holds them that way throughout the lift. With the legs out of the movement, the hamstrings, glutes, and lower back have to do the bulk of the work. The hips are higher at the start, the torso is more horizontal, and the bar is typically lowered with a greater hip hinge before returning to standing. It looks similar to a Romanian deadlift but is usually performed from the floor rather than from the hang.

Loading differs substantially. A lifter's stiff-leg deadlift is typically 65-80% of their conventional — the reduction in leg contribution caps how much can be moved. That is not a weakness of the exercise; it is the point. Trying to match conventional numbers on a stiff-leg pull almost always forces the knees to bend, which makes it a conventional deadlift in disguise.

Training carryover runs both directions. Stiff-leg deadlifts build hamstring and lower-back strength that supports the conventional pull off the floor and through the mid-range. Lifters whose conventional deadlift stalls because the bar comes off the floor slowly or their back rounds in the mid-range often benefit from a stiff-leg cycle. Going the other way, conventional strength provides the pulling capacity that makes any stiff-leg variation more productive.

Program both if you have the time. Conventional deadlifts as the primary heavy pull, stiff-leg variations as a targeted accessory for posterior-chain weak points. Most intermediate and advanced lifters run them in different sessions or different weeks because both are systemically demanding.

Conventional deadlift for absolute strength and the competition lift itself. Stiff-leg deadlift as an accessory to build hamstring and lower-back strength at longer muscle lengths.