Back extension: how to do it
Main muscles: Erector spinae (lower back). Helpers: Gluteus maximus, Hamstrings. Below: step-by-step form, common mistakes, a muscle map, reps and rest, and what to swap it for.
Equipment
Bench
Reps
10–15
Rest
75 s
Muscle group
Back
How to do it
- Pads under the hips, feet fixed, hands on the chest.
- Lower to about 90° while keeping the back flat.
- Come up in line with the torso and stop there.
Common mistakes
Hyperextending at the top, jerking, rounding the back at the bottom.
Muscles worked
primary·secondary
- Primary
- Erector spinae (lower back)
- Secondary
- Gluteus maximus, Hamstrings
A secondary muscle gets roughly half the stimulus of a set — that is also how the log’s stats count it.
Alternatives: similar exercises
Deadlift
Barbell · Erector spinae (lower back), Gluteus maximus, Hamstrings, Semitendinosus
Good morning
Barbell · Hamstrings, Erector spinae (lower back), Gluteus maximus
Romanian deadlift
Barbell · Hamstrings, Semitendinosus, Gluteus maximus
Sumo deadlift
Barbell · Gluteus maximus, Rectus femoris, Hip adductors (inner thigh), Erector spinae (lower back)
Back squat
Barbell · Rectus femoris, Vastus lateralis (outer quad), Vastus medialis (teardrop), Gluteus maximus
Superman
Bodyweight · Erector spinae (lower back)
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