A standing desk is the one desk intervention people actually spend money on, so it deserves a straight answer. It is not the health device it was sold as in 2015, and it is not the fad the backlash made it either. It does one thing reliably, one thing modestly, and several things not at all.
The useful framing is that it does not replace sitting with something better. It replaces one held position with the option of two, and the option is where the value is.
The short answer
- Sitting time: it works. Sit-stand desks cut workplace sitting, on low-quality evidence.
- Back discomfort: modest reduction, meta-analysed.
- Health outcomes: unproven. No trial has run long enough on hard endpoints.
- Standing all day has its own cost — prolonged standing is associated with developing low back symptoms.
- The version that survives the evidence is alternating, which the desk enables rather than guarantees.
What a standing desk changes
Start with the outcome the trials measure best, which is behaviour rather than health.
Shrestha and colleagues' Cochrane review of workplace interventions for reducing sitting, updated in 2018, found sit-stand desks reduce sitting time at work in the short term — on the order of an hour or more a day in some trials — and rated the evidence low quality, with effects on musculoskeletal symptoms unclear and little known about whether the change persists past a year.
Agarwal, Steinmaus and Harris-Adamson meta-analysed the discomfort question in Ergonomics in 2018 and found sit-stand workstations reduced low back discomfort in office workers. Modest effect, small trials, self-reported outcome.
Grade: moderate for the behaviour change, weak for the discomfort benefit, absent for hard health outcomes. Nobody has followed standing-desk users for long enough to know whether the sitting they displaced translates into anything.
Standing is also a held position
The part the marketing skipped is that the alternative has its own literature, and it is not flattering.
Coenen and colleagues reviewed the laboratory and field evidence on occupational standing in the British Journal of Sports Medicine in 2018 and found prolonged standing associated with the development of low back symptoms — in some laboratory protocols, a substantial proportion of previously symptom-free people develop back pain within two hours of continuous standing. Waters and Dick reviewed the wider occupational evidence in Rehabilitation Nursing in 2015 and reported associations between prolonged standing at work and lower limb complaints, varicose veins and back pain.
Grade: reasonably solid that prolonged standing is its own exposure. Which is the whole point. If the problem with sitting is that it is one position held for hours, then standing for hours is the same problem in a different shape.
This is why the honest recommendation is not "stand instead". It is alternate, in blocks short enough that neither position becomes the held one.
How long to stand
No trial has established the correct ratio, and every number you have seen is somebody's rule of thumb.
What can be said:
- Change position before it becomes uncomfortable, not after. Discomfort is the signal that the exposure has run long, and by then you have had the exposure.
- Blocks of 20 to 40 minutes sit inside the range used in the studies that measured discomfort, and are short enough that neither position dominates.
- Standing is not activity. The metabolic trials that found real effects used walking, two minutes every 20 minutes — Dunstan and colleagues in Diabetes Care in 2012 — not standing still. Standing burns marginally more than sitting and is not a substitute for movement.
- Build up. People who go from a full sitting day to a mostly standing one in a week usually report foot, calf and back complaints, and then quit. Add an hour a week.
What it will not do
It will not correct your posture. Standing has as many bad shapes available as sitting does, and the underlying claim — that habitual posture drives symptoms — is much weaker than the advice implies. Richards and colleagues found no association between measured sitting neck posture clusters and neck pain in over 1,000 adolescents, and Swain and colleagues found no consensus in the reviews on posture and low back pain. Posture correction exercises grades this properly.
It will not offset a sedentary life. Ekelund and colleagues' pooled analysis of over a million adults in The Lancet in 2016 found the sitting–mortality association largely attenuated by 60 to 75 minutes a day of moderate activity. Standing at a desk is not that activity, and describing a desk as a health intervention on the strength of that literature is a category error.
It will not fix ankle and calf stiffness — it will find it. Standing for hours loads the calves and ankles in a way sitting does not, and people with limited ankle dorsiflexion notice it first.
The one thing it demands of you
Ankles. A day mostly on your feet asks more of ankle dorsiflexion, calf length and foot tolerance than a day in a chair does, and that is the one area where a measurement is genuinely useful before you change your working posture.
The knee-to-wall test is the instrument for it, and it is the only test in Limber's battery that produces a real measured length: big toe at the wall, heel down, knee driven forward until it touches, then walk the foot back until it will not. Record the centimetres on each side.
Two facts about that scale, published because a page proves them. One centimetre is worth 5 to 10 points on the app's 0–100 scale — 10 points through the middle (4 cm reads 35, 6 cm reads 55) and 5 at the top (10 cm reads 85, 11 cm reads 90). And Limber calls a 12-point gap between sides an imbalance. So a centimetre of careless foot placement manufactures most of an imbalance out of nothing, which is why the protocol matters more here than on any other test in the battery.
The Range Score composes that reading with the rest and leaves unmeasured ground drawn as unmeasured. Take a reading before you change your desk and again three weeks after; Limber's default re-test interval is 21 days, adjustable to 14 or 28.
So is it worth buying
If you can afford it and you will actually alternate, yes — modestly, for the reason the evidence actually supports: it gives you a second position and makes changing between them cheap. That is a real benefit and it is smaller than the price tag implies.
If the plan is to stand all day, no. You are trading one held position for another with its own association with back pain.
And if the plan is to buy the desk instead of moving, it is the most expensive way to not go for a walk. The micro-breaks research covers what the movement is actually worth, and desk setup and mobility covers the rest of the furniture question, which is smaller than the furniture industry suggests.
If back or leg pain is the reason you are considering one: pain radiating down a leg, numbness, weakness, pain after a fall, or back pain with fever, unexplained weight loss or a change in bladder or bowel control needs a clinician who can examine you, not a purchase. Nothing here diagnoses anything and nothing here is treatment.
The cluster is desk and posture.
Questions
Are standing desks actually worth it?
For reducing workplace sitting, yes — a Cochrane review found sit-stand desks cut sitting time, on low-quality evidence. For low back discomfort, a meta-analysis found a modest reduction. For hard health outcomes, nothing has been shown, because no trial has run long enough. Worth it if you alternate; not worth it as a health purchase.
How long should I stand at a standing desk?
No study has established the right ratio. Blocks of 20 to 40 minutes, changed before discomfort rather than after, sit inside the tested range. Build up gradually — going from a full sitting day to a mostly standing one inside a week is how most people end up with sore feet and an expensive sitting desk.
Is standing all day better than sitting all day?
No. Prolonged standing has its own association with low back symptoms, and in laboratory protocols a substantial share of previously symptom-free people develop back pain within about two hours of continuous standing. The problem with both is the same: one position, held.
Does a standing desk burn more calories?
Marginally, and not enough to matter. The difference between sitting and standing is small; the difference that showed up in controlled trials came from short walking breaks rather than from standing still. Treating a standing desk as exercise is the mistake its marketing encouraged.
Will a standing desk help my back pain?
Possibly a little. The meta-analysis of sit-stand workstations found reduced low back discomfort, on modest evidence with self-reported outcomes. It is not a treatment. Back pain that radiates into a leg, comes with numbness or weakness, or followed an injury needs a clinician who can examine you.
What should I measure before switching to standing?
Ankle dorsiflexion, on both sides, with the knee-to-wall test. A mostly standing day asks considerably more of the ankles and calves than sitting does, and it is the one reading that predicts whether the change will feel manageable in the first fortnight.