Compression socks, plainly explained — for legs that don't get to sit down
By the end of a 12-hour shift, gravity has been working against you the whole time. Here's how graduated compression helps, what the mmHg numbers actually mean, and when to check with a doctor first.
What "graduated compression" actually does
Stand or walk for hours and blood starts to pool in your lower legs — that's just gravity doing its thing. By the back half of a shift it shows up as heavy, aching, swollen legs and feet that feel two sizes too big.
Graduated compression socks are knitted tightest at the ankle and ease off as they go up the calf. That gradient gently nudges blood back up toward the heart instead of letting it settle. A clinical review in the CMAJ found graduated compression measurably increases deep-vein blood-flow velocity, which is the whole point: keep things moving so less fluid pools by hour ten. Nurses report less end-of-shift swelling, less leg fatigue, and easier recovery before the next day on.
This is an educational explainer, not medical advice. If you have a vascular condition, treat the section below seriously and talk to a clinician.
Compression levels in mmHg
Pressure is measured in millimetres of mercury (mmHg), and socks are labelled as a range — the span of pressure applied at the ankle. Higher isn't automatically better; the right level depends on your legs.
Mild support for tired legs; gentle, easy to wear.
A sensible first pair. Real circulatory support without feeling restrictive across a full shift.
Most-recommended for 12-hour shifts, noticeable swelling, spider/varicose veins.
Stronger, prescription-territory. Use under clinician guidance.
Picking a pair without overthinking it
A simple way to choose, written for someone who just wants to stop their feet throbbing by hour eight.
Start at 15-20 mmHg if you're new
If your legs are just tired and a little puffy, this is the reasonable starting point. Meaningful support, low commitment.
Step up to 20-30 mmHg for real swelling
Walking 4-5 miles a shift on hard floors, visible end-of-shift swelling, or early varicose veins? This is the level most nurses settle on.
Measure in the morning, before swelling
Sizing is by ankle and calf circumference, not shoe size. Measure early when your legs are at their smallest so the fit is right.
Put them on first thing
Pull them on before the shift, before your legs swell. They're easiest to get on dry, fresh legs and do the most good worn all day.
Replace them when the stretch goes
Elastic fatigues. Once a pair stops feeling firm at the ankle, it's stopped doing its job — rotate in a fresh pair.
Talk to a doctor first if any of these apply
Compression is safe for most people on their feet all day — but for some legs it's the wrong call, and a clinician should weigh in before you wear it.
Peripheral artery disease (PAD)
Severe PAD (an ankle-brachial index under about 0.5) is a contraindication — compression can further reduce blood flow. Mild-to-moderate PAD needs a clinician's judgement, not a guess.
Diabetes or neuropathy
Reduced sensation means you may not feel a sock that's too tight or rubbing. Get sizing and pressure checked by a professional first.
30-40 mmHg and above
Firmer medical-grade levels are meant to be worn on a clinician's advice, with specific sizing — not bought off a shelf on a hunch.
New swelling in one leg, redness, or pain
Sudden one-sided swelling can signal something that needs assessing, not compressing. Get it looked at before reaching for socks.
I ignored the swelling for two years and called it 'just the job.' First week in a proper 20-30 pair, I walked to my car at the end of a night shift and my feet didn't feel like bricks. Wish someone had told me sooner.
Honest answers
Do compression socks really help, or is it marketing?
For people standing and walking all day, the mechanism is real and reviewed in the clinical literature: graduated compression increases deep-vein blood-flow velocity and reduces pooling. Nurses consistently report less swelling and leg fatigue. It's support, not a cure for an underlying vein condition — but for tired, heavy legs it does measurable work.
What level should I buy if I'm not sure?
15-20 mmHg is the safe starting point for mild tired/puffy legs. If you have noticeable end-of-shift swelling or early varicose veins, 20-30 mmHg is what most nurses on 12-hour shifts land on. Go above 30 mmHg only on a clinician's advice.
Can I wear them every shift?
Most people wear them all day, every working day, putting them on before the shift starts. Keep a few pairs in rotation, wash them regularly, and replace them once the ankle no longer feels firm.
Is it ever a bad idea?
Yes — with severe peripheral artery disease, certain diabetic or neuropathy situations, or sudden one-sided leg swelling, compression can be the wrong choice. When in doubt, check with a doctor. Official guidance from bodies like the NHS and CDC is a good neutral starting point.
Comfort is a workforce issue, not a perk
Sore legs, skipped breaks, and burnout all live on the same floor. We build plainspoken resources for the people who never leave it — and the teams trying to look after them.