Do both. Romanian deadlifts as your primary hamstring builder through hip extension. Leg curls to train knee flexion and isolate the hamstrings.
Leg curls isolate knee flexion function, while RDLs emphasize hip extension. Complete hamstring development requires both movement patterns.
Choose leg curls when you want to isolate the hamstrings, target knee flexion specifically, or perform high-rep hamstring work without back fatigue. Leg curls are excellent for hamstring pump, injury prevention, and addressing hamstring weakness relative to quads.
Choose Romanian deadlifts when you want to build hamstring strength and size through the hip hinge, improve posterior chain development, or strengthen your deadlift. RDLs work the hamstrings at the hip joint and build functional strength.
| Category | Lying Leg Curl | Romanian Deadlift |
|---|---|---|
| Joint Action | Knee flexion isolation | Hip extension focus |
| Movement Type | Machine isolation | Free weight compound |
| Posterior Chain | Hamstrings only | Hamstrings, glutes, back |
| Lower Back Load | None | Moderate to high |
| Best For | Hamstring isolation | Hamstring strength + size |
Choose leg curls when you want to isolate the hamstrings, target knee flexion specifically, or perform high-rep hamstring work without back fatigue. Leg curls are excellent for hamstring pump, injury prevention, and addressing hamstring weakness relative to quads. For programming, Lying Leg Curl works well for 10-15 reps for muscle growth or 6-8 reps for strength development.
Choose Romanian deadlifts when you want to build hamstring strength and size through the hip hinge, improve posterior chain development, or strengthen your deadlift. RDLs work the hamstrings at the hip joint and build functional strength. For programming, Romanian Deadlift is typically performed for 8-12 reps for hypertrophy or 4-6 reps for strength.
On leg day, do RDLs (3-4x8-10) early when fresh. Finish with leg curls (3x12-15) for isolation. This covers both hamstring functions: hip extension and knee flexion.
You want isolated knee flexion work, have a fatigued lower back from other exercises, or need higher-rep hamstring training without hip hinge demands.
You want complete posterior chain development, functional pulling strength, and carryover to deadlifts. RDLs build more total muscle.
You want complete hamstring development. RDLs for hip extension strength; leg curls for knee flexion isolation.
Leg curls and Romanian deadlifts both build hamstring muscle but through different mechanisms. RDLs provide a loaded stretch and train hip extension. Leg curls isolate knee flexion. For complete hamstring development, include both exercises.
Beginners can start with leg curls because they are simpler to perform and do not require hip hinge technique. Romanian deadlifts require proper form to avoid lower back strain. Learn the hip hinge with light weight before loading RDLs heavy.
Replacing Romanian deadlifts with leg curls limits posterior chain development and functional strength. Leg curls only train knee flexion while RDLs build total hamstring and glute strength. Use both for complete hamstring training.
Romanian deadlifts isolate hamstrings with constant tension, while conventional deadlifts build total-body pulling strength. Use both for complete posterior chain development.
Barbell squats build more total-body strength and functional fitness, while leg press allows heavier quad loading with less technical demand. Choose based on your goals and mobility.
Both squats and deadlifts are essential for complete strength development. Squats prioritize quads while deadlifts emphasize the posterior chain. Include both for optimal results.
Dumbbell bench press offers greater range of motion and muscle balance, while barbell bench press allows heavier loads for strength. Use both for optimal chest development.
Both Lying Leg Curl and Romanian Deadlift appear in our hamstrings training plans. MySetPlan programs the right exercises for your goals with proper sets, reps, and progressive overload.
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