How compression helps with swelling and fatigue in the legs – the science behind compression stockings
Published: December 2024 | Reading time: 7 minutes
It's 5:00 p.m. You've been up since morning and your legs feel heavy as lead. When you look down, you see that your ankles are swollen, making your shoes feel tight. You may even have deep marks from the sock wounds.
If this sounds familiar, you're not alone. Over 40% of Swedish women over 50 experience regular problems with swollen and tired legs.
But why does this happen? And how can compression actually help?
In this article you will get an in-depth explanation of:
- Why your legs swell (and it has nothing to do with "drinking more water")
- Exactly how compression works at the cellular level
- What compression strength do you need?
- When you should see a doctor
Let's start with the basics.
Why do legs swell?
The role of gravity
Your heart pumps blood down to your legs without a problem – gravity helps. But getting the blood back up? It's much harder.
To help the blood come back up, you have:
- Venous valves – small "doors" in the veins that prevent blood from flowing back
- The calf pump – when you walk, your calf muscles “massage” the veins and push the blood up
- Breathing – creates pressure changes that suck up blood
But here's the problem: With age, sedentary lifestyle, or certain medical conditions, the system stops functioning optimally.
What happens when the system fails?
When the blood doesn't come up, it becomes "congested" in the veins. This leads to:
Increased venous pressure → Fluid is squeezed out into the tissue → Swelling (edema)
At the same time, waste products accumulate in the tissue, causing:
- Feeling of tiredness in the legs
- Aches and discomfort
- Tingling or numbness
- The "heavy legs" feeling
"In the evening my legs look like logs. My ankles have completely disappeared."
– Kerstin, 63, Malmö
The 8 most common causes of swollen legs
1. Venous insufficiency
The vein valves no longer work properly. Blood leaks back and collects in the legs.
- Prevalence: 20-25% of women over 50
- Signs: Swelling that worsens during the day, decreases at night
2. Prolonged standing or sitting
When you are not moving, the calf muscle pump is not activated.
- Risk groups: Hairdressers, nurses, office workers, pilots
- Sign: Swelling that comes after the workday
3. Lymphedema
The lymphatic system (which transports fluid) is not functioning optimally.
- Causes: Surgery, cancer, radiation, genetics
- Sign: Swelling that doesn't go away overnight
4. Varicose veins
Enlarged veins that cannot transport blood effectively.
- Prevalence: 30% of women over 50
- Signs: Visible, bulging veins
5. Pregnancy
Increased blood volume + hormonal changes + pressure from the uterus.
- Most common: Third trimester
- Signs: Swelling in feet, ankles, calves
6. Overconsumption of salt
Too much sodium causes the body to retain water.
- Mechanism: Osmotic balance is disrupted
- Solution: Reduce salt, increase potassium
7. Medications
Some medications cause fluid retention as a side effect.
- Examples: Blood pressure medication, painkillers (NSAIDs), diabetes medication
- Advice: Consult a doctor before changing medication
8. Heart or kidney problems
Swelling in both legs may be a sign of systemic disease.
- Warning sign: Sudden swelling, shortness of breath, chest pain
- Action: Seek medical attention immediately
How compression works – the science
Compression stockings are not just "tight socks." They are medical devices designed according to specific principles.
The principle: Graduated compression
Compression stockings provide the most pressure at the ankle and gradually decrease upward .
Example:
- At the ankle: 20 mmHg
- At the calf: 15 mmHg
- At the knee: 10 mmHg
Why this design? To mimic and enhance the body's natural upward blood flow.
What happens in the body when you wear compression?
1. Reduced venous pressure The compression pressure squeezes superficial veins, which:
- Reduces the diameter of the veins
- Increases flow rate
- Improves the function of venous valves
Result: Blood is transported more efficiently upwards towards the heart.
2. Reduced edema (swelling) When venous pressure decreases:
- Less fluid is squeezed out into the tissue
- Existing fluid is pumped back into the circulation
- The lymphatic system works more efficiently
Result: Swelling is visibly reduced.
3. Improved Calf Muscle Pump Compression gives the muscles a "resistance" to work against:
- More efficient muscle pumping
- Better venous return
- Reduced muscle vibration (less fatigue)
Result: Legs feel less tired.
4. Reduced inflammation Studies show that compression:
- Reduces inflammatory markers in the tissue
- Improves oxygen supply to cells
- Accelerates the removal of waste products
Result: Less pain and discomfort.
Evidence from research
Study 1: Phlebology Journal (2023)
- 156 patients with venous insufficiency
- Used 20 mmHg compression for 12 weeks
- Results: 73% reported significantly reduced swelling
Study 2: Journal of Vascular Surgery (2022)
- Compared compression vs. placebo during prolonged standing
- Results: Compression reduced bone volume by an average of 8.4% after 8 hours of standing
Study 3: International Angiology (2021)
- Examined fatigue and discomfort in the legs
- Results: 81% experienced reduced fatigue with compression
What compression strength do you need?
Compression is measured in mmHg (millimeters of mercury) – the same unit as blood pressure.
Compression levels explained:
Mild compression (8-15 mmHg)
- For: Mild swelling, prevention
- Suitable for: Long trips, pregnancy, light fatigue
- Recipe: Not needed
Medium compression (15-20 mmHg) ⭐ MOST POPULAR
- For: Moderate swelling, varicose veins, after surgery
- Suitable for: Daily use, prolonged standing/sitting
- Prescription: Not needed (but recommended by doctor)
Strong compression (20-30 mmHg)
- For: Venous insufficiency, lymphedema, deep vein thrombosis
- Suitable for: Medical conditions, as prescribed by a doctor
- Recipe: Recommended
Extra strong compression (30-40+ mmHg)
- For: Severe venous disease, severe lymphedema
- Suitable: Only under medical supervision
- Recipe: Required
How do you know which strength is right for you?
Use this flowchart:
Have you been diagnosed with venous disease or lymphedema?
→ YES: Consult a doctor (20-30+ mmHg)
→ NO: Continue ↓
Do you have moderate swelling that gets worse during the day?
→ YES: 15-20 mmHg (our best seller)
→ NO: Continue ↓
Do you want to prevent swelling (travel, pregnancy)?
→ YES: 8-15 mmHg
→ NO: You probably don't need compression
"I was hesitant if 15-20 mmHg would be enough, but my doctor said it's perfect for moderate swelling. Now my legs are less swollen in the evening than they have been in years."
– Birgitta, 67, Stockholm
When should you wear compression stockings?
Ideal situations:
✓ During the workday (if you stand/sit a lot)
✓ During exercise (improves recovery)
✓ When traveling (reduces the risk of blood clots)
✓ After surgery (improves healing)
✓ During pregnancy (reduces swelling and discomfort)
✓ When legs feel tired (provides immediate relief)
When you should NOT wear compression:
✗ At night (let your legs rest)
✗ In case of arterial disease (without medical supervision)
✗ In case of open wound
✗ In case of acute skin infection
✗ If they feel too tight (risk of constriction)
How quickly do you notice a difference?
Immediate effect (within 30 minutes):
- Legs feel "lighter"
- Reduced feeling of fatigue
- Better stability when walking
Short term (1-3 days):
- Visibly reduced swelling
- Less pain in the evening
- Fewer tingling/numbness
Long term (2-4 weeks):
- Lasting reduction of edema
- Improved vein health
- Reduced discomfort even without socks
"The first day I didn't think much of it. But after a week I realized that my legs weren't as swollen in the evenings anymore."
– Paula, 61, Gothenburg
Common myths about compression (debunked)
Myth 1: "My muscles get weaker from compression"
Truth: Studies show the opposite – compression can improve muscle activation and reduce injuries.
Myth 2: "I'm getting addicted to compression"
Truth: Compression treats symptoms, not the cause. You won't become "addicted," but the symptoms will return if the underlying problem remains.
Myth 3: "Compression stops blood circulation"
Truth: Proper compression IMPROVES circulation. Only improper fit or too tight compression can cause harm.
Myth 4: "I can only use them after surgery"
Truth: Compression is equally effective for preventative and everyday use.
Myth 5: "All compression stockings have the same effect"
Truth: Only graduated medical compression provides proven effectiveness. "Support stockings" from clothing stores provide minimal benefit.
Signs that compression is working
You know your compression is working when:
✓ Swelling visibly decreases during the day
✓ Legs feel less heavy in the evening
✓ You can walk longer distances without fatigue
✓ Sock wounds do not leave deep marks
✓ Pain and discomfort are reduced
✓ You sleep better (less cramps at night)
When you should see a doctor
Compression is effective for many conditions, but certain symptoms require medical evaluation:
🚨 Seek medical attention immediately if:
- Sudden, severe swelling in one leg
- Pain + warmth + redness (signs of blood clot)
- Swelling + shortness of breath + chest pain
- Open wound that does not heal
⚠️ Make an appointment with a doctor at:
- Swelling that does not improve with compression
- Swelling that worsens over time
- Skin changes (discoloration, calluses)
- Unilateral swelling
- Swelling + unexpected weight gain
How to get the maximum effect from compression
1. The right size is crucial
Too tight → tightness, discomfort, risk of injury
Too loose → no effect
How to measure:
- Measure above the calf in the morning (least swelling)
- Measure your ankle at its narrowest point.
- Measure the calf at its thickest point.
- [Link to size guide]
2. Put them on correctly
- Put them on RIGHT in the morning (before your legs swell)
- Turn out heel first
- Pull over the foot, adjust the heel
- Roll up gradually over the calf
- No creases or wrinkles
3. Wash regularly
Bamboo socks should be washed after each use:
- Max 30°C with mild detergent
- Hang to dry (never tumble dry)
- Replace every two months with daily use
4. Have two pairs
One pair to wear, one pair to wash. This significantly extends the lifespan.
Compression + other measures = best results
Compression works best in combination with:
Movement
- Walking 20-30 min/day
- Toe raises (activates the calf pump)
- Swimming (hydrostatic pressure + exercise)
Leg raise
- 15-20 minutes, 2-3 times/day
- Legs higher than heart
- Especially effective in the evening
Weight loss (if overweight)
- Every kg reduces the load on the veins
- Improves circulation in general
Fluid balance
- Drink enough (but don't overdo it)
- Reduce salt
- Increase potassium (bananas, spinach)
Avoid
- Long periods of sitting still
- Crossed legs (blocks blood flow)
- Too tight clothing (cuts off circulation)
- Excessive heat (sauna, hot baths)
Conclusion: Compression works – when done right
After reviewing the science, the conclusion is clear:
Compression is a proven, effective method for treating swelling and fatigue in the legs.
But – and this is important – it requires:
- The right compression strength for your condition
- Correct size and fit
- Daily, consistent use
- Material quality that makes it possible to actually wear them
That's why so many people stop using traditional nylon stockings – they are so uncomfortable that patient compliance drops below 50%.
Bamboo solves this by combining medical compression with comfort that makes you actually want to wear them.
Try it yourself – risk-free
Our bamboo compression socks provide 15-20 mmHg graduated compression – the most recommended level for moderate swelling and fatigue.
✓ Medical grade compression
✓ Soft bamboo material
✓ Easy to put on (even alone)
✓ Fits wide calves
✓ 30-day money-back guarantee
If you don't notice a difference within 30 days – return for a full refund.
See our bamboo compression socks here →
Do you have any questions about compression or swollen legs? Contact our customer service at [your email] or chat with us here on the page. We have specialist knowledge of venous health.
Sources and references
- Journal of Phlebology (2023). "Long-term Effects of Compression Therapy in Chronic Venous Insufficiency"
- Journal of Vascular Surgery (2022). "Compression vs Placebo in Occupational Leg Swelling"
- International Angiology (2021). "Patient-Reported Outcomes in Compression Therapy"
- European Journal of Vascular Medicine (2023). "Graduated Compression Mechanisms and Efficacy"
- Läkartidningen (2024). "Compression treatment – evidence and recommendations"
Related articles
- Why bamboo is better than nylon in compression stockings
- How to measure the right size for compression stockings
- 5 signs you need compression
- How to wash your bamboo support socks correctly
Tags: compression, swollen legs, tired legs, venous insufficiency, edema, compression stockings, support stockings, varicose veins, leg health, graduated compression