Low back pain (non-specific)

What it is

Non-specific low back pain means the ache is real but no imaging finding explains it. That is not a cop-out diagnosis - it is the honest one for roughly 90 percent of back pain. Discs bulge, joints wear and muscles tire in people with no pain at all, so a scan showing those things does not identify the culprit.

What is usually going on instead is a load problem. The deep muscles that hold the spine steady have lost endurance, the hips have stiffened so they stop sharing the work, and the back has spent years being asked to bend and hold rather than to be strong. The pain is the system complaining about the mismatch, not a report of damage.

What it feels like

• A dull, spread-out ache across the low back rather than a sharp point you can put a finger on
• Worse after sitting for a long stretch, and worse again in the first minute of standing up
• Stiff and sore for the first ten or twenty minutes of the morning, then easier once you move
• Flares after a day of bending - gardening, unloading a car, bathing small children
• Sometimes spreads into the buttock or the back of the thigh, but stops above the knee

What causes it

Most people have more than one of these at once, and they feed each other. Read the list looking for the two or three that sound like your week rather than for the one true answer — the ones that describe you are the ones worth acting on.

Endurance loss in the deep trunk muscles

Transverse abdominis, the multifidus alongside each vertebra and the obliques are meant to hold a low, steady contraction all day. They lose that stamina long before they lose strength, so the spine gets slightly less support in hour six than in hour one - which is exactly when the ache arrives.

Glutes that have stopped doing their share

The glutes are the largest hip extensors and are meant to drive every lift and every step up. Sitting keeps them lengthened and idle, and when they under-contribute the lumbar erectors extend the hip by tipping the pelvis instead. The back does the glutes' job all day and aches by evening.

Stiff hips passing the movement upward

Bending forward should be mostly hip movement. When the hips will not fold, the missing range gets taken from the lumbar spine, so every bend to pick something up flexes the low back further than it was designed to go. Tight hip flexors do the same in reverse, tilting the pelvis forward and compressing the joints at the back of the spine.

Hours in sustained flexion

Sitting slumped, driving, and looking down at a phone all hold the lumbar spine in flexion for long unbroken stretches. Discs creep under a constant load and the muscles behind them stay stretched and quiet, so standing up feels like unfolding something that has set.

A stiff mid-back that will not rotate

The thoracic spine is built to twist and is held still for hours. The rotation it gives up is taken by the lumbar spine, which is built for stability instead. This is why a genuinely stiff upper back shows up as low back pain.

One big day after many small ones

Most flares are not caused by the thing that happened - they are caused by the eleven months of nothing before it. A body that has been asked for very little all year meets a day of moving furniture with no reserve, and the tissue tolerance is simply exceeded.

Poor sleep and a nervous system on alert

Sleep loss, stress and low mood measurably lower pain thresholds. The same mechanical load hurts more in a bad week. This is not the pain being imaginary; it is the volume control being turned up on a real signal.

Fear of movement after the first episode

The first bad back teaches people to guard. Guarding means moving less, moving stiffly and avoiding loading - all of which weaken exactly the muscles that would have prevented the next one. This is the single biggest predictor of an episode turning into a long-term problem.

Carrying more weight than the trunk is trained for

Extra abdominal mass sits in front of the spine and increases the leverage the back muscles have to fight all day. It is a load problem rather than a moral one, and it responds to strengthening the trunk as much as to changing the load.

A previous episode

The strongest single risk factor for low back pain is having had it before. Each episode leaves slightly less strength, slightly more caution and slightly more sensitivity, which is why the useful goal is not curing this one but making the next one smaller.

Who tends to get it

• Anyone who sits for most of the working day, especially with no reason to stand up
• People whose jobs involve repeated bending and lifting - care work, warehousing, trades, parenting small children
• Anyone who has had an episode before; recurrence is the norm rather than the exception
• People going through a stressful or sleep-deprived period, which lowers the threshold at which the same load hurts
• Adults who have never trained the trunk or the hips, which is most adults

What makes it worse, and what settles it

The qFIT routine for this

Ready-made routineBack Pain/Bulletproofing

qFIT already has this one built. It runs massage first, then stretching, then strength — the order that works on a body that is already sore — and every activity in it carries the reason it is there.

The button below opens your Checklist with this routine already selected, so instead of your whole list you land on just its Categories, Targets and Exercises, each with its checkbox, ready to tick as you work through them.

Have more than one problem? Tick yours under My Problems on My Profile and your Checklist's Routine list gains Recommended for my problems — every routine for the problems you picked, merged into one. Your picks stay private; that filter is the only thing they feed.

Get it checked if…

Bowel or bladder change; saddle numbness; progressive leg weakness; fever; unexplained weight loss; night pain; major trauma; cancer history - urgent referral

And whatever the body part: chest pain or unusual breathlessness on exertion; a fever alongside the pain; unexplained weight loss; pain that is constant and unrelated to how you move; new numbness, weakness or loss of bladder or bowel control; or one calf that is swollen, warm and painful. Any of those, stop and get assessed.

How it usually goes

Most single episodes settle substantially within two to six weeks whatever you do, which is why almost any treatment can appear to work. What actually changes the long run is what you do between episodes: people who keep moving, build trunk endurance and get their hips strong have fewer, shorter and milder recurrences. Expect improvement to be uneven rather than linear - a good week, a bad day, a better fortnight - and judge progress by the month rather than by the morning.

Prevalence basis: GBD 2021: #1 cause of years-lived-with-disability worldwide; 57% of all primary-care musculoskeletal visits

Others the same routine covers

These share the Back Pain/Bulletproofing routine, so the work is the same. If one of them also sounds like you, that is a reason to expect more from it, not less.

This is general information, not a diagnosis, and it cannot examine you. If it matches you, use it to ask better questions of a clinician rather than to replace one.