Heavy, aching legs at the end of the day feel like they want warmth. They don’t. Heat is one of the few things that reliably makes varicose veins and end-of-day leg swelling worse.
Cool water, elevation and compression are what help. This is a case where the instinct and the physiology point in opposite directions. The general rule it sits under: heat or ice: a physio’s decision guide.
Why warmth makes it worse
Varicose veins are veins whose one-way valves have stopped closing properly, so blood pools instead of being pushed back up the leg. The ache, the heaviness and the swelling all come from that pooling.
Heat widens veins.
A wider vein with a failing valve pools more, not less. That’s why legs feel worse after a hot shower, a long soak, a sauna, or a hot day, and why people with varicose veins often notice their symptoms peak in the evening. It’s the same reason heat is wrong on fresh swelling generally: see hot or cold compress for swelling. The same logic rules heat out for a limb at risk of lymphoedema.
What helps instead
- Elevate. Legs above heart height for 15 minutes, a few times a day. Two pillows under the ankles, not under the knees.
- Compression stockings, properly fitted. The single most useful thing for most people, and worth getting measured rather than guessing a size.
- Walk. Your calf muscle is the pump that returns blood up the leg. Standing still is worse than walking; sitting all day is worse than both, and long flights are their own case: back pain after a long flight.
- Cool water over the legs at the end of a shower.
- Calf raises at your desk, ten or twenty at a time.
Where heat is still fine
Having varicose veins doesn’t mean heat is banned everywhere. A pad on your lower back for a stiff back is unaffected, and so is one on your neck and shoulders. Keep it off the varicose areas themselves, and off legs that are swollen at the time. The wider list of exclusions: who should not use a heating pad.
Night cramps in the calf are a separate problem with a different answer: tight calves and night cramps. So are cold feet, where the same caution about heat on the lower legs applies.
Skin over varicose veins burns more easily
Long-standing venous problems change the skin around the ankle: thinner, discoloured, sometimes itchy or hardened. That skin damages at lower temperatures than healthy skin and heals badly once it does. The risk is the same one behind the diabetes rules, and the care needed is the same as for any fragile skin.
Never put a heat pad, a hot water bottle or a heat rub on discoloured ankle skin. Venous leg ulcers are slow, miserable things, and a burn is one of the ways they start.
Swelling that isn’t from veins
Not all leg swelling is venous, and some causes are urgent:
- One calf swollen, warm and tender, especially after a flight, surgery or bed rest. That can be a blood clot. Same-day medical attention, no heat, no massage. See also after a knee replacement.
- Swelling in a limb after lymph node surgery or radiotherapy, which is lymphoedema and has its own rules: lymphoedema and heat.
- Both legs swelling with breathlessness, which can point to the heart. See a doctor.
- Sudden swelling with redness and fever, which can be infection.
See a doctor if…
- The skin around your ankle is darkening, hardening or breaking down
- A varicose vein bleeds, or becomes hard, red and painful
- An ulcer or sore on the lower leg isn’t healing
- The ache is limiting what you do
Varicose veins are treatable, and the treatments have moved well beyond stripping. A vascular assessment is the right next step if stockings and walking aren’t enough.
Clinically reviewed by: Nigel Chua (Hand Occupational Therapist) & Louise Yow (Physiotherapist). This article is general information, not a diagnosis. electricheatpad.com sells electric heat pads.
