SEATED LEG EXTENSION MACHINE
The only movement that completely isolates knee extension and fully shortens the rectus femoris without hip involvement.
QUICK FACTS: SEATED LEG EXTENSION MACHINE
help_outline What is the Seated Leg Extension Machine?
The Seated Leg Extension Machine is a isolation (single-joint) exercise designed to build the Quadriceps (Rectus Femoris & Teardrop Medialis). The only movement that completely isolates knee extension and fully shortens the rectus femoris without hip involvement.
fitness_center What muscles does it work?
Primary Target: Quadriceps (Rectus Femoris & Teardrop Medialis).
Secondary Synergists: Vastus Lateralis, Vastus Intermedius.
handyman What equipment is required?
Required Equipment: Selectorized Seated Leg Extension Station with Adjustable Shind Pad.
check_circle Is it suitable for beginners?
Rated Beginner. Beginners can safely perform this by starting with 3 sets of 12-15 reps (RPE 7), maintaining a controlled 3-second descent, and focusing on form before increasing weight.
play_circle MOVEMENT DEMONSTRATION
analytics ANATOMICAL BLUEPRINT
list_alt STEP-BY-STEP BIOMECHANICAL EXECUTION
Machine Pivot & Pad Alignment
Adjust backrest so the knee joint lines up precisely with the machine's red rotational axis pin. Adjust lower pad across lower shins.
Grip Handles & Hip Anchor
Grasp side handles firmly and pull your hips down hard into the seat.
Smooth Extension to Lockout
Extend knees smoothly to full straight-leg extension, squeezing quads violently at the peak.
2-Second Controlled Negative
Lower weight stack over 2 seconds back to 90° bend without letting stack slam.
checklist FORM TECHNIQUE PARAMETERS
warning COMMON MISTAKES & PRECISION FIXES
RECOMMENDED ALTERNATIVES & VARIATIONS FOR SEATED LEG EXTENSION MACHINE
Need a substitute exercise? Whether swapping between free-weight dumbbells, barbells, or commercial gym machines, here are the most biomechanically comparable movements:
RELATED LEGS MOVEMENTS
Single Heavy Dumbbell
Dumbbell Goblet Squat
QUADRICEPS FEMORIS
Pair of Heavy Dumbbells
Dumbbell Romanian Deadlift (RDL)
HAMSTRINGS (SEMITENDINOSUS & BICEPS FEMORIS)
Elevated Step / Ledge, Single Dumbbell
Single-Leg Dumbbell Calf Raise
GASTROCNEMIUS (DIAMOND CALF)
Single Heavy Dumbbell
Dumbbell Plie / Sumo Squat
VASTUS MEDIALIS (TEARDROP) & ADDUCTORS
ADD SEATED LEG EXTENSION MACHINE TO YOUR ROUTINE
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