Leg extension
A machine isolation exercise that straightens the knee to train the quadriceps.
- Muscle group: Legs
- Equipment: Machine
- Difficulty: Beginner
Also known as: Machine leg extension, Quad extension, Lårstræk, Knæstræk, Benstræk
How to do it
- Adjust the seat so your knees line up with the pivot and the pad rests on your lower shins.
- Extend the legs until almost straight, squeezing the thighs.
- Lower slowly without letting the stack crash.
Common mistakes
- Kicking the weight up with momentum.
- Lifting the hips off the seat.
Alternatives
Watch a video demonstration on YouTube
“How To: Leg Extension (Cybex)” by ScottHermanFitness (opens YouTube)
Used in the programmes
- Push / pull / legs 6-day6 days a week
- Hypertrophy 4-day split4 days a week
- Legs focus (gym)3 days a week
- Upper / lower hypertrophy 4-day4 days a week
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General technique guidance, not individual advice. Stop if something hurts and talk to a professional about injuries.