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Quadriceps Femoris

Four-headed anterior thigh muscle group (rectus femoris, vastus lateralis, vastus medialis, vastus intermedius). Primary knee extensor. Exhibits high morphological variability with additional heads present in 64.1% of limbs studied.

Draft95%

Anatomy

Origin: Rectus femoris: AIIS (straight head) and ilium above acetabulum (reflected head); Vasti: various surfaces of femoral shaft
Insertion: Patella via quadriceps tendon, then tibial tuberosity via patellar ligament
Action: Knee extension; rectus femoris also assists hip flexion
Innervation: Femoral nerve (L2-L4)
Blood Supply: Lateral femoral circumflex artery, femoral artery branches

Movements (2)

Movement	Joint	Role	Notes
Knee Extension	Tibiofemoral Joint	Primary	Group reference
Hip Flexion	Hip Joint (Coxofemoral)	Synergist	Via rectus femoris

Exercises (69)

Exercise	Role
Wall Sit	Primary
Bear Crawl	Primary
Terminal Knee Extension (TKE)	Primary
Eccentric Stair Descent	Primary
Quadriceps Strengthening (SLR / Terminal Knee Extension)	Primary
Neuromuscular Exercise (Step-Downs / Single-Leg Balance)	Primary
Spanish Squat (Belt-Assisted)	Primary
Leg Press (Limited ROM, 0-60°)	Primary
Split Squat / Bulgarian Split Squat	Primary
Box Jump (Bilateral)	Primary
Depth Jump (Drop Jump)	Primary
Lateral Bounds (Single-Leg)	Primary
Power Clean (Hang Variation)	Primary
Overhead Squat (Assessment & Training)	Primary
Single-Leg Hop Tests (Return-to-Sport Battery)	Primary
Sit-to-Stand	Primary
Step-Up Variations (Forward, Lateral, Cross-Over)	Primary
Seated Knee Extension (Bodyweight)	Primary
Step-Up on Stairs	Primary
Single Leg Squat / Pistol Squat	Primary
Knee Split Squat Isometric Holds	Primary
Wall Ball Squat	Primary
Backwards Walking	Primary
Eccentric Step-Down	Primary
Lateral Step-Up	Primary
Forward Lunge	Primary
Single-Leg Sit-to-Stand	Primary
Back Squat (Barbell)	Primary
Front Squat	Primary
Goblet Squat	Primary
Reverse Lunge	Primary
Leg Extension	Primary
Countertop-Supported Squat	Primary
Wall Sit Isometric	Primary
Squat	Primary
Burpee	Primary
Walking Lunges with Trunk Rotation	Primary
Jump Squat	Primary
Mountain Climber	Secondary
Couch Stretch (Rectus Femoris / Hip Flexor)	Secondary
Jumping Jack	Secondary
Downward Dog (Adho Mukha Svanasana)	Secondary
Knee-to-Wall Ankle Mobilization	Stabilizer
Standing Calf Stretch on Step	Stabilizer
Cook Hip Lift (Single-Leg Bridge with Contralateral Hip Flexion)	Stabilizer
Lateral Band Walk (Monster Walk)	Stabilizer
Standing Figure-4 Stretch	Stabilizer
Standing Hamstring Stretch (Foot on Step)	Stabilizer
Standing Hip Circles	Stabilizer
Supine Hamstring Stretch (Strap-Assisted)	Stabilizer
Straight Leg Raise	Stabilizer
Chair-Supported Single-Leg Balance	Stabilizer
Tandem Stance Balance	Stabilizer
Stair Calf Raise	Stabilizer
World's Greatest Stretch	Stabilizer
Hollow Body Hold	Stabilizer
Hip Thrust	Stabilizer
Calf Raise off Stair Edge	Stabilizer
Heel-Toe Walking / Tandem Gait	Stabilizer
Hip Abduction/Extension with Sliders	Stabilizer
Single Leg Hip Hinge with Bench	Stabilizer
Heel-to-Toe Walk	Synergist
Backpack Weighted Carry	Synergist
Wall Hamstring Stretch	Synergist
Standing Quad Stretch	lengthening
Towel Hamstring Curl	lengthening
Mindfulness-Integrated Stretching	lengthening
Hamstring and Calf Strengthening	lengthening
Leg Curl	lengthening

Sources

Kinesiology of the Musculoskeletal System: Foundations for Rehabilitation — Anatomy of Quadriceps Femoris — origin, insertion, action, innervation
Muscles: Testing and Function with Posture and Pain — Manual muscle testing for Quadriceps Femoris