The single-arm stiff-legged deadlift is a dumbbell exercise that targets the hamstrings, glutes, lower and upper back, and core. The difference between a stiff-legged deadlift and a Romanian deadlift is primarily the amount of knee bend. The knees are only slightly bent in a stiff-legged deadlift, while they bend more in a Romanian deadlift. Stiff-legged deadlifts are generally performed for low to moderate reps, such as 8-10 reps per set, with a focus on maximizing the hamstring stretch rather than moving heavy weight. Feel free to wear a weight belt to protect your lower back.