Compression therapy uses controlled external pressure, typically on the legs, to improve blood flow back toward the heart, reduce swelling, and support healing. It’s one of the most widely used treatments in vascular medicine, prescribed for conditions ranging from varicose veins to leg ulcers to blood clot prevention. The pressure is delivered through stockings, bandages, wraps, or inflatable devices, and the type you use depends on what’s being treated.
How Compression Therapy Works
Your veins have one-way valves that push blood upward against gravity. When those valves weaken or fail, blood pools in the lower legs, pressure builds inside the veins, and fluid leaks into surrounding tissue. That’s what causes the swelling, heaviness, and skin changes associated with venous disease.
Compression therapy counteracts this by applying graduated pressure, strongest at the ankle and decreasing as it moves up the leg. This does several things at once: it speeds up venous blood flow, reduces the backward leaking (reflux) through damaged valves, increases pressure in the tissue to push leaked fluid back into circulation, and improves lymph drainage. The net effect is less swelling, better circulation, and a lower risk of complications like skin breakdown or blood clots. A stocking applying roughly 20 mmHg of pressure at the ankle is enough to measurably increase blood flow velocity and prevent leg swelling after prolonged sitting or standing.
Conditions Treated With Compression
Compression therapy is used across a surprisingly wide range of conditions:
- Chronic venous insufficiency: the most common indication, where weakened vein valves cause persistent swelling, skin discoloration, and leg fatigue.
- Varicose veins: compression helps relieve the swelling and pain associated with enlarged, twisted veins.
- Deep vein thrombosis (DVT): compression is used both to prevent clots in people at risk (such as after surgery) and alongside blood thinners in people who already have a clot.
- Leg ulcers and wounds: compression accelerates healing by reducing the fluid buildup that slows tissue repair.
- Lymphedema: when the lymphatic system can’t drain fluid properly, compression helps move it mechanically.
- Orthostatic hypotension: for people whose blood pressure drops when they stand, compression pushes blood from the legs back toward the heart.
A 2024 set of clinical guidelines covering seven categories of venous disease made 30 recommendations for compression use. Seven of those were graded as strong recommendations, reflecting solid evidence behind the therapy’s core applications.
Types of Compression Devices
Compression Stockings
These are the most familiar form: elasticated garments that slide onto the leg and provide steady, sustained pressure. They come in different lengths (knee-high, thigh-high, full pantyhose) and pressure classes. Stockings are convenient for daily wear and are the standard choice for managing chronic venous insufficiency, preventing swelling during long periods of sitting or standing, and maintaining results after more intensive treatment.
Short-Stretch Bandages
Unlike stockings, which are elastic and stretch significantly, short-stretch bandages extend to less than 100% of their original length. This stiffness is actually the point. When you walk, your calf muscles push against the rigid bandage, creating high pressure peaks that act like a rhythmic massage on the veins. Between steps, the pressure drops back down, making the bandage tolerable at rest. This pulsing action is particularly effective for severe swelling and active leg ulcers. Zinc paste bandages are an even more rigid version of the same concept.
Intermittent Pneumatic Compression Devices
These are mechanical pumps that wrap inflatable cuffs around the leg and fill them with air in a timed sequence. The chambers inflate and deflate at set intervals, mimicking the pumping action of walking. They’re commonly used in hospitals after surgery to prevent blood clots in patients who can’t get up and move. Outside the hospital, they serve as a useful addition to standard compression for people with lymphedema, limited mobility, or arterial problems that make constant compression risky. Devices vary in where they apply pressure (calf, thigh, or foot), how long each inflation cycle lasts, and how much pressure they deliver.
Who Should Avoid Compression
Compression therapy is safe for most people, but it can be dangerous when blood flow to the legs is already severely restricted. The main concern is peripheral artery disease, where narrowed arteries can’t deliver enough blood to the legs. Adding external pressure on top of that can push an already struggling limb toward tissue damage.
An international consensus statement identifies several situations where sustained compression should not be used: severe peripheral artery disease (specifically when the ankle-brachial index falls below 0.6, ankle pressure is under 60 mmHg, or toe pressure is under 30 mmHg), severe heart failure, confirmed allergy to compression materials, and severe diabetic nerve damage where the patient can’t feel pain or pressure changes. For anyone with even mildly impaired leg circulation (an ankle-brachial index below 0.9), the effects of compression on blood supply should be carefully monitored.
Daily Wear and Practical Challenges
There’s no universally agreed-upon number of hours per day you should wear compression. The typical recommendation is “during waking hours,” and most guidance defaults to something close to an 8-hour workday. One study found that wearing stockings for 10 hours a day was more effective at preventing swelling than 6 hours, suggesting that longer wear times offer a real benefit for people on their feet or sitting for extended periods.
The bigger challenge is getting people to stick with it. Compression garments cause itching, sweating, skin dryness, and irritation, especially in warm weather. Some people find them uncomfortable regardless of the season. These side effects are the primary reason patients stop wearing their stockings, which is a problem because venous conditions are chronic and compression only works while you’re using it. Choosing the right pressure level and garment style, and making sure the fit is correct, can make a meaningful difference in comfort and long-term compliance.
Getting the Right Fit
Compression stockings need to be sized to your leg, not picked off a shelf by shoe size. Standard fitting involves measurements at multiple points: the ankle, base of the calf, widest part of the calf, below the knee, and (for thigh-high garments) at the mid-thigh and upper thigh. These measurements determine both the size and the shape of the stocking. A poorly fitted garment can create pressure points, bunch behind the knee, or slide down, all of which reduce effectiveness and make you less likely to wear it. Many pharmacies and medical supply stores offer professional fitting, and your prescriber can guide you toward the appropriate pressure class.
Compression for Athletic Recovery
Compression garments have become popular among athletes for post-exercise recovery, though the evidence is more mixed than the marketing suggests. The most consistent finding is a modest reduction in muscle soreness after exercise: out of 50 studies examining this, 29 found compression reduced soreness while 22 found no effect. For muscle pain specifically, six of nine studies showed a benefit.
Where the evidence falls flat is lactate clearance, the idea that compression helps your body clear metabolic waste faster after exercise. Of 40 studies looking at blood lactate levels, the vast majority found no effect from wearing compression. Seven found a small benefit, and three actually found higher lactate with compression. So if you find compression sleeves or tights comfortable after a hard workout, they may help with soreness, but they’re not flushing waste products from your muscles in any meaningful way.