Compression sleeves are snug, elastic garments that apply graduated pressure to a limb or body part, helping push blood and fluid back toward the heart. They’re used across a wide range of situations, from managing chronic swelling conditions like lymphedema to preventing blood clots after surgery to helping athletes recover faster. The type you need and how much pressure it applies depends entirely on what you’re using it for.
How Compression Sleeves Work
Compression sleeves apply the most pressure at the point farthest from your heart (your ankle or wrist) and gradually decrease pressure as the sleeve moves up the limb. This gradient design works with your body’s circulatory system, encouraging blood and lymph fluid to flow upward rather than pooling in your extremities. The result is reduced swelling, improved circulation, and less strain on your veins.
Pressure is measured in millimeters of mercury (mmHg), the same unit used for blood pressure. Sleeves range from light (15 to 20 mmHg) for mild everyday use to very firm (50 to 60 mmHg) for severe medical conditions. The higher the number, the tighter the squeeze.
Managing Lymphedema
One of the most common medical uses for compression sleeves is lymphedema, a condition where lymph fluid builds up in a limb and causes persistent swelling. This frequently happens after cancer treatment, particularly breast cancer surgery that involves removing lymph nodes. Compression sleeves help prevent fluid from accumulating and keep swelling under control after initial treatment reduces it.
For lymphedema, sleeves are classified into four pressure levels. Class 1 (20 to 30 mmHg) and Class 2 (30 to 40 mmHg) work for milder cases and are available off the shelf. Class 3 (40 to 50 mmHg) and Class 4 (50 to 60 mmHg) are custom-ordered for more severe swelling. Some manufacturers also offer lighter options at 15 to 20 mmHg for very mild cases. European-manufactured sleeves follow a slightly different classification system with lower pressure thresholds at each class level, so check the actual mmHg rating rather than relying on the class number alone.
Preventing Blood Clots After Surgery
Compression sleeves and stockings are a standard part of post-surgical care because they significantly reduce the risk of deep vein thrombosis (DVT), a potentially dangerous blood clot that forms in the deep veins of the legs. When you’re immobile during and after surgery, blood flow slows and clots become more likely.
A Cochrane review of eight randomized trials involving nearly 1,300 surgical patients found that compression stockings cut the rate of DVT roughly in half, from 26% in patients without compression to 13% in those wearing it. That means for every eight surgical patients who wear compression, one DVT case is prevented. In hospital settings, these devices are typically worn 18 to 20 hours a day, removed only briefly for bathing and skin checks.
Treating Varicose Veins and Poor Circulation
Varicose veins develop when valves inside leg veins weaken and allow blood to flow backward and pool. This pooling causes the bulging, twisted veins visible under the skin, along with aching, heaviness, and swelling. Compression sleeves (usually knee-high stockings for this purpose) counteract the pooling by providing external pressure that supports those weakened valves.
Compression therapy improves blood circulation in the lower legs, ankles, and feet, reducing the pain and swelling associated with varicose veins. Beyond symptom relief, consistent compression can also help heal ulcers and wounds caused by chronic blood pooling, a complication of untreated venous insufficiency that can become serious over time.
Supporting POTS and Blood Pressure Disorders
People with postural orthostatic tachycardia syndrome (POTS), a condition where standing up causes an excessive spike in heart rate, often use compression as part of their daily management. The problem in POTS is that blood drops too quickly into the legs upon standing, forcing the heart to race to compensate.
Waist-high compression tights have shown strong results for POTS. In a community-based trial reviewed by the American College of Cardiology, participants wearing compression had a standing heart rate of about 105 beats per minute compared to 119 without it. After several hours of wear, heart rates were even lower (84 versus 89 bpm), and symptom scores improved significantly. These benefits held even for participants already taking heart rate medications, making compression a useful addition rather than a replacement for other treatments. For POTS specifically, waist-high garments outperform knee-high sleeves because they compress the large blood volume in the thighs and abdomen.
Athletic Recovery
Compression sleeves are widely marketed to athletes, and the evidence supports some of those claims, particularly for recovery. During high-intensity exercise, your muscles produce lactate as a byproduct. Compression garments help clear that lactate faster by increasing blood flow, which shuttles it to the liver, heart, and resting muscles where it can be processed.
Research published in the Journal of Strength and Conditioning Research found that athletes wearing compression garments during active recovery after high-intensity running had lower lactate levels and lower heart rates compared to those in regular shorts. The practical takeaway: compression likely won’t make you run faster, but wearing it during cooldowns and in the hours after hard exercise may reduce soreness and speed recovery.
Pressure Levels and What They’re For
Choosing the right compression level matters. Too little pressure won’t help, and too much can restrict blood flow.
- 15 to 20 mmHg (light): Mild leg fatigue, minor swelling from travel or prolonged sitting, early-stage varicose veins, everyday athletic recovery.
- 20 to 30 mmHg (moderate, Class I): Moderate varicose veins, mild lymphedema, post-surgical DVT prevention, pregnancy-related swelling.
- 30 to 40 mmHg (firm, Class II): More advanced venous insufficiency, moderate lymphedema, active DVT treatment, healed venous ulcers.
- 40 to 50+ mmHg (very firm, Class III and above): Severe lymphedema and advanced venous disease. These are custom-fitted and require medical guidance.
Who Should Not Use Compression
Compression is not safe for everyone. The main concern is peripheral artery disease (PAD), where arteries in the legs are narrowed or blocked. Adding external pressure on top of already restricted arterial flow can cause tissue damage.
Clinicians use the ankle-brachial index (ABI), a ratio comparing blood pressure in the ankle to blood pressure in the arm, to determine whether compression is safe. If the ABI falls below 0.8, high compression (30 to 40 mmHg) is not recommended. For people with mixed venous and arterial disease (ABI between 0.5 and 0.8), reduced compression around 23 to 30 mmHg may still be used with medical oversight. If the ABI drops below 0.5, compression should be avoided entirely. Other conditions that can make compression risky include skin infections, severe neuropathy where you can’t feel whether the sleeve is too tight, and congestive heart failure where redistributing fluid toward the heart could be dangerous.
Getting the Right Fit
A compression sleeve that doesn’t fit properly can cause problems, from bunching that creates pressure points to rolling at the edges that acts like a tourniquet. For leg sleeves, you’ll typically need to measure the circumference of your ankle, calf, and thigh at specific points, along with the length of your leg. For arm sleeves, measurements at the wrist, forearm, and upper arm are standard. Take measurements first thing in the morning before any swelling sets in during the day.
Off-the-shelf sleeves at 15 to 30 mmHg work well for many people when sized correctly. Higher-pressure garments (Class III and above) are almost always custom-made from professional measurements. Compression garments lose their elasticity over time, so most need replacing every three to six months with regular daily wear. Having two pairs and alternating them extends the life of each.