S-Posture: How to Fix S-Posture in Your Golf Swing
Setup·Reviewed April 20, 2026·By Coach Harvey - AI Golf Coach
At address, the lower back is excessively arched and the pelvis is tilted forward, creating an S-shape in the spine when viewed from the side. The setup loads the lumbar spine and tends to produce loss of posture or early extension during the swing. To fix it: at address, the pelvis is in neutral with the lower back showing a normal lordotic curve — not flat, not exaggerated. Hip hinge from the hips, not from the lumbar spine.
S-posture at address means the lower back is excessively arched and the pelvis tilts forward, creating an S-shape in the spine when viewed from the side. The lower back is loaded with extension before the swing even starts.
The downstream problem is twofold. First, the player tends to lose posture or early-extend during the swing because the starting position is unstable. Second, repeated reps load the lumbar spine in a way that causes back pain over time.
The fix is teaching a neutral pelvis at address — pelvis level, normal lumbar curve, hip hinge from the hips rather than from the lower back.
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What Causes S-Posture
01Misunderstood 'Stick the Butt Out' Cue
Teaching pros sometimes use 'stick your butt out' to describe hip hinge at address. Players interpret it as an exaggerated arch — pushing the hips back and arching the lumbar spine. The cue meant hip hinge; the result is S-posture.
The correct interpretation is a hinge from the hip joints with the spine in its normal curve, not an arched extension.
02Tight Hip Flexors
Long hours of sitting shorten the hip flexors, which pull the pelvis into forward tilt automatically. Players with desk jobs often have S-posture without trying — it's just how their pelvis sits.
Hip flexor mobility work over 2-4 weeks usually allows a neutral position to feel natural.
How to Fix S-Posture — Step by Step
Diagnose — Side Mirror Check
Stand sideways to a mirror in your address posture. The lumbar curve should be normal — not flattened, not arched. If you see a deep arch or a forward-tilted pelvis, you have S-posture.
Feel — Pelvic Tilt
Stand in address. Practice tilting the pelvis backward (tucking the tailbone slightly under). Most players who normally arch find that 'tucking' produces a neutral position.
Mobility — Hip Flexors
Add daily hip-flexor stretches (couch stretch, kneeling lunge with overhead reach). 5 minutes per side, daily, for 2-4 weeks.
Do I Have S-Posture?
Answer these questions based on your most recent range session or video review.
When filmed from the side at address, does your lower back show a deep arch?
Does your pelvis tilt forward at address (hips back and up)?
Do you frequently feel lower-back tightness or pain after practice or play?
Have you been told to 'stick your butt out' more at address?
Drills
01Pelvic Tilt at Address
- 1.Stand sideways to a mirror in your address posture.
- 2.Tilt your pelvis forward (exaggerated arch) — note the S-shape.
- 3.Now tilt the pelvis backward (tuck the tailbone) — note the rounded shape.
- 4.Find the middle: a normal lumbar curve, not arched, not flat.
- 5.Hold the neutral position for 10 seconds, then make a slow practice swing maintaining the position.
- 6.Repeat 10 times.
A neutral spine — neither arched nor rounded. The lower back is engaged but not stressed.
Tucking too far. The goal is neutral, not flat. A flat lower back at address creates its own problems (C-posture).
02Couch Stretch for Hip Flexors
- 1.Kneel in front of a couch or low wall.
- 2.Place the top of your trail foot on the couch behind you, with your knee on the ground at the base of the couch.
- 3.Step your lead foot forward into a lunge position.
- 4.Tuck your tailbone slightly to lengthen the hip flexor of the kneeling leg.
- 5.Hold for 60 seconds.
- 6.Switch sides and repeat.
A stretch along the front of the hip and thigh of the kneeling leg. Sometimes intense; should not be sharp.
Letting the lower back arch to escape the stretch. The point of tucking the tailbone is to target the hip flexor — backing off defeats the purpose.
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S-Posture — Drill Card
coachharvey.ai/faults/s-posture
1. Pelvic Tilt at Address
Equipment: Mirror · Reps: 10 reps before every range session
- Stand sideways to a mirror in your address posture.
- Tilt your pelvis forward (exaggerated arch) — note the S-shape.
- Now tilt the pelvis backward (tuck the tailbone) — note the rounded shape.
- Find the middle: a normal lumbar curve, not arched, not flat.
- Hold the neutral position for 10 seconds, then make a slow practice swing maintaining the position.
- Repeat 10 times.
Feel: A neutral spine — neither arched nor rounded. The lower back is engaged but not stressed.
Avoid: Tucking too far. The goal is neutral, not flat. A flat lower back at address creates its own problems (C-posture).
2. Couch Stretch for Hip Flexors
Equipment: Couch or wall · Reps: 60 seconds per side, daily
- Kneel in front of a couch or low wall.
- Place the top of your trail foot on the couch behind you, with your knee on the ground at the base of the couch.
- Step your lead foot forward into a lunge position.
- Tuck your tailbone slightly to lengthen the hip flexor of the kneeling leg.
- Hold for 60 seconds.
- Switch sides and repeat.
Feel: A stretch along the front of the hip and thigh of the kneeling leg. Sometimes intense; should not be sharp.
Avoid: Letting the lower back arch to escape the stretch. The point of tucking the tailbone is to target the hip flexor — backing off defeats the purpose.
Common Misdiagnoses
You think you have a loss of posture during the swing., Loss of posture is often a downstream effect of S-posture. The starting position is unstable, so the body abandons it under load.
Fix the setup first. If the loss of posture clears up once the setup is neutral, S-posture was the cause.
Read about Loss of Posture →How You Know It’s Fixed
Pelvis neutral at address, normal lumbar curve, hip hinge from the hips rather than from the lower back. Easier to maintain posture through the swing.
Frequently Asked Questions
Should I be teaching myself a flat-back posture instead?
No. A flat lower back is C-posture — the opposite extreme. The target is neutral: a normal lumbar curve, neither arched nor flat. Both extremes cause problems; the middle is where you want to be.
Related Faults
These flaws often appear alongside s-posture and may share a root cause.
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