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Dumbbell Leg Extension
Seated isolation exercise using a dumbbell between the feet to target quadriceps through knee extension, building thigh strength and hypertrophy as a machine alternative for home workouts.
About Exercise
Equipment
Dumbbells
Difficulty
2/5 • Beginner
Primary Muscle Groups
Quads
Secondary Muscles
Hip Flexors, Abs
Accessory Muscles
Glutes, Hamstrings
Popularity Score
5
Goals
Training Style
Setup Requirements
Requires Rack
No
Requires Bench
Yes
Requires Spotter
No
Space Needed
Small
Noise Level
Low
Muscle Breakdown
View Muscle MapQuads
10/10Rectus Femoris, Vastus Lateralis, Vastus Medialis
Hip Flexors
4/10Iliopsoas
Abs
3/10Glutes
2/10Hamstrings
2/10Programming
Typical Rep Range
10-20 reps
Rest Between Sets
60-90 seconds
How to Perform
Sit on the edge of a stable bench with back straight and core engaged. Bend knees to 90 degrees and secure a dumbbell vertically between your feet by squeezing them together.
- Brace your core and maintain upright torso.
- Exhale and extend legs forward, straightening knees without locking.
- Squeeze quadriceps at the top and pause briefly.
- Inhale and lower legs slowly to starting position.
- Repeat for desired reps, keeping movement controlled.
Coaching Tips
Form Cues
- Squeeze quads hard
- Knees track straight
- Back stays neutral
- Feet grip tight
- Control the descent
Breathing
Inhale as you lower the weight; exhale forcefully as you extend your legs.
Tempo
3-1-2
Range of Motion
Start from knees bent at 90 degrees; extend to nearly straight legs without knee lockout; lower until shins nearly touch the floor.
Safety
Safety Notes
- Avoid if acute knee pain or instability
- Start with light weight to test grip
- Stop if joint discomfort occurs
- Use strap if dumbbell slips easily
- Consult professional for pre-existing knee issues
Spotting
Not required; perform solo with focus on control and secure setup.
Common Mistakes
- Using momentum to swing weight
- Locking knees at top
- Arching lower back
- Dropping weight too fast
- Insecure dumbbell hold
When to Avoid
- Acute knee injuries
- Knee joint instability
- Severe arthritis in knees
Flexibility Needed
- Adequate knee flexion to 90 degrees
- Basic hip mobility for seated position
Build Up First
- Familiarity with knee extension movement
- Ability to sit stably without back support
Also known as
Seated Dumbbell Leg Extension, DB Leg Extension
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