FitnessAIBack extensions
Home › Exercises › Lower back › Back extensions
How to do it
Rise until your torso lines up with your legs, without hyperextending; the glutes finish the movement
Muscles worked
Mainly lumbar. Train it inside a balanced routine to progress safely.
Recommended sets and reps
As a compound lift, it fits in 3–5 sets of 5–12 reps leaving 1–3 reps in reserve (RIR). Prioritize it at the start of the session, when you're fresh.
Common mistakes to avoid
- Hyperextending the lower back at the top of the movement instead of finishing in a neutral position.
- Using too much weight at the cost of technique and full range of motion.
- Doing reps too fast, without controlling the eccentric (lowering) phase.
Alternative exercises
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Frequently asked questions
What muscles does Back extensions work?
Back extensions mainly works the lumbar muscle group, plus synergist and stabilizer muscles depending on the variation.
How many sets of Back extensions should I do?
Between 3 and 5 sets per session, adjusting the total weekly volume for lumbar to your level (about 10–20 sets per muscle per week).
Is Back extensions good for building muscle?
Yes. Combined with progressive overload, good technique and enough rest, it's an effective tool to grow lumbar.
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