Compression socks and stockings.

Normal: you can see the ankle bone, and the hollow between it and the Achilles tendon, the thick cord at the back of your ankle.

Example of swelling: the ankle, the top of the foot and the lower calf look a little fuller, and the hollow beside the ankle bone fills in. The dashed line shows the usual shape.

Some people experience swelling or heaviness in their lower legs, particularly after prolonged sitting or standing. You might notice shoes that feel tight, or legs that feel heavy at the end of the day.

Foot. Blood in your foot has to travel all the way up your leg on its way back to your heart. The dashed line follows a vein that starts on the top of your foot and runs up the inside of your leg.

Why your ankles matter. Swelling can be especially noticeable around the ankles and feet. Compression garments are designed to provide graduated support around the lower leg.

Calf. The calf muscles play an important role in helping move blood back toward the heart as you walk. They're joined to your heel by the Achilles tendon, so they work every time you push off with your foot. The next question shows how.

Swelling that is significant, in one leg only or has no clear cause should be checked by a doctor first. When to get help

Sitting: when you sit or stand still for a long time, your calf muscles aren't tightening and relaxing the way they do when you walk, so they do less to help blood travel back up from the lower legs.

1. 1 Foot on the ground. Your foot lands and takes your weight.
2. 2 Calf tightens. As you push off, your calf muscles tighten and pull on the Achilles tendon to lift your heel.
3. 3 Veins are squeezed. The working muscle presses on the veins deep inside your calf.
4. 4 Blood moves up. That squeeze helps move blood up toward your heart. Valves in the vein then shut so it doesn't sink back down.
5. 5 Calf relaxes. As your leg swings forward, your calf relaxes and the veins fill again from below.
6. 6 And again. Every step repeats the cycle. That's one reason walking is good for your legs.

A simplified illustration, not a medical simulation.

Your ankle is the lowest part of your leg, where swelling tends to show first. A graduated sock gives the most support there, and less as it goes up.

Simplified illustration. The actual pressure depends on the sock and on how well it fits your leg.

Outside view: a compression sock on the lower leg.

Inside view: the calf muscle and the veins, with the sock's compression layer around them. Your calf still does the pumping. The sock's steady pressure gives your calf muscles something firm to squeeze against as they tighten, and for some people it can help stop fluid from settling around the ankles.

Compression provides graduated support around the lower leg, which can help some people manage swelling, heaviness and other symptoms.

Calf muscle: it tightens with each step and squeezes the veins deep in your calf.

Veins: they carry blood up the leg toward your heart. Small valves inside them shut behind it so it doesn't sink back.

Compression: the sock gives support from the outside, firmest at the ankle.

Normal veins: the veins in your legs have small flaps, called valves, that open only one way. They let blood pass up toward your heart and shut if it starts to sink back.

Varicose vein example: if the valves in a vein no longer shut fully, blood can pool there. Over time the vein can widen and twist.

Compression doesn't remove varicose veins or repair them. Whether compression is appropriate depends on the individual. Speak with a healthcare professional for personalized advice.

Simplified illustration. It can't show whether you have varicose veins.

Long day standing

Standing for most of the day can contribute to feelings of heaviness, aching or swelling in some people. Standing still also means your calf muscles aren't squeezing and relaxing the way they do when you walk.

Long periods sitting

When you sit for a long time, your calf muscles aren't doing much work. Staying in one position for long stretches can contribute to leg discomfort or swelling.

Travel

Long flights, train rides and drives mean hours of sitting in a small space, which can affect how your legs feel by the time you arrive. When you can, get up and walk around.

Swelling

Swelling can be especially noticeable around the ankles and feet, and you may notice it more at the end of the day. Swelling that is significant, in one leg only or has no clear cause should be checked by a doctor first.

Varicose veins

Varicose veins can sometimes be associated with aching, heaviness or swelling. Compression garments may be recommended for some people to help manage symptoms.

Active lifestyle

Walking keeps your calf muscles working. Some people also choose compression for comfort and support during activity, and needs differ between people.

Compression may be appropriate for some people. None of these situations means you automatically need it.

• Your ankles or feet often swell, or your legs feel heavy by the end of the day.
• You have varicose veins.
• You stand, sit or travel for long hours.
• You've been advised to wear compression socks or stockings.
• You're not sure whether compression socks are right for you.
• You're coming in for foot or ankle care and want to ask about compression socks.

If compression socks suit you, we measure your legs, including your ankles and calves, then order socks to fit.