Lying Single Leg Extension
Lying Single Leg Extension Exercise Description
Lying Single Leg Extension is an open-chain knee extension performed on your back to isolate the quadriceps of one leg at a time. The movement straightens the knee primarily with the rectus femoris and vastus group (lateralis, medialis, intermedius), while the trunk muscles and hip flexors stabilize the pelvis and keep the thigh steady. Executing it supine lets you focus on clean knee mechanics—moving only at the tibiofemoral joint—without loading the spine. Because you extend the knee against gravity with the lower leg, it emphasizes control near terminal extension and smooth, controlled flexion on the return. Keep alignment consistent so the knee tracks in line with the toes and the pelvis stays level throughout.
- Muscle Groups: Quads
- Target Muscles: Vastus Intermedius, Vastus Lateralis, Vastus Medialis
- Assisting Muscles: Rectus Femoris
- Stabilizing Muscles: External Obliques, Iliacus, Internal Obliques, Psoas Major, Transversus Abdominis
- Body Area: Lower Body
- Body Parts: Legs, Upper Legs
- Body Surface: Front, Inner, Side
- Body Symmetry: Unilateral
- Equipment: Bodyweight
- Exercise Patterns: Other
- Exercise Type: Strength
- Functional Grouping: Knee Extensors
- Joint Involvement: Single-joint
- Muscle Location: Deep Quad, Inner Quad, Outer Quad
- Movement Direction: Other
- Muscle Position: Anterior, Lateral, Medial
- Gender: Male
How To Do The Lying Single Leg Extension Exercise
‘- Lie supine. Bend the non‑working leg, foot flat. Brace lightly to maintain a neutral spine.
– On the working side, flex the hip and knee to about 90°, thigh vertical.
– Keep the thigh still; dorsiflex the ankle and point toes up.
– Exhale and extend the knee until the leg is nearly straight—avoid forced hyperextension.
– Pause briefly; inhale and flex the knee back to ~90° with control.
– Maintain pelvis level and ribs down; avoid arching, hip hiking, or thigh drift.
– Keep the knee aligned with the second toe; move through a comfortable, pain‑free range.
– Switch sides, repeating the same alignment and control.
Lying Single Leg Extension Tips
‘- Bend the non-working leg with the foot flat to help you brace and keep a neutral spine.
– Set the working thigh vertical with the hip and knee at about 90° before you start.
– Keep the working thigh still and only move at the knee throughout the exercise.
– Dorsiflex the ankle on the working leg so your toes point up as you extend.
– Exhale as you extend the knee until it’s nearly straight, avoiding forced hyperextension.
– Pause briefly at near-full extension before returning.
– Inhale and flex the knee back to about 90° with smooth, controlled motion.
– Keep your pelvis level and ribs down; avoid arching your back, hip hiking, or thigh drift.
– Track the knee in line with the second toe and move only through a comfortable, pain‑free range.
– When switching sides, match the same setup, alignment, and control on the other leg.
Lying Single Leg Extension Beginner Introduction
Lying Single Leg Extension is a controlled, single-leg thigh exercise performed while lying on the back. One leg moves while the other stays grounded, helping isolate the front of the working thigh as the knee straightens and bends. The movement centers on the knee joint, with the lower part of the leg lifting and lowering, while the hips and core create a steady base so the thigh of the active leg stays mostly in place.
Because the body rests on the floor, there is no added load through the spine, allowing attention on how the knee moves rather than on balance. The end portion of straightening the leg is emphasized, along with a smooth return as the knee bends again. Throughout the motion, the pelvis remains even, the ribs stay quietly anchored, and the knee follows the same general path as the toes. This creates a simple environment for practicing precise knee alignment, steady hip position, and calm, deliberate control of each repetition.