What causes swollen and heavy calves upon waking in the morning?

Generally, waking up in the morning with swollen and heavy legs may be caused by improper sleeping posture, excessive exercise the previous day, lower limb varicose veins, deep vein thrombosis (DVT), heart failure, or other reasons. It is recommended to seek medical attention promptly, identify the underlying cause, and receive symptomatic treatment under a doctor's guidance. Specific explanations are as follows:

1. Improper sleeping posture: Prolonged supine or side-lying positions during sleep can compress the lower leg, impairing local blood circulation. This may lead to leg swelling and heaviness upon waking. Adjusting sleeping posture, avoiding prolonged pressure on one leg, and slightly elevating the legs before bedtime can promote venous return and relieve discomfort.

2. Excessive exercise the previous day: Engaging in prolonged physical activities such as running or brisk walking can cause calf muscle fatigue and accumulation of metabolic waste products, leading to a feeling of swelling and heaviness in the morning. Performing proper stretching after exercise and engaging in light walking or applying heat to the calves upon waking can improve blood circulation and reduce discomfort.

3. Lower limb varicose veins: Abnormal function of venous valves impairs blood return, causing blood to pool in the leg veins. This results in morning leg swelling and heaviness, which worsens after prolonged standing. Patients may take medications such as micronized purified flavonoid fraction (MPFF) tablets, diosmin tablets, or calcium dobesilate capsules as prescribed to improve venous function.

4. Deep vein thrombosis (DVT): Formation of a blood clot in the deep veins of the leg obstructs venous return, causing morning leg swelling and heaviness, often accompanied by tenderness and increased skin temperature. Patients should follow medical advice to take anticoagulant medications such as warfarin sodium tablets, rivaroxaban tablets, or dabigatran etexilate capsules.

5. Heart failure: Reduced cardiac pumping function leads to systemic venous congestion and blood pooling in the lower limbs, resulting in morning leg swelling and heaviness. Symptoms may also include shortness of breath and fatigue. Patients should take medications such as furosemide tablets, spironolactone tablets, or digoxin tablets as directed to improve heart function and reduce congestion.

In daily life, avoid prolonged sitting or standing; get up regularly to move the legs; reduce fluid intake before bedtime to prevent worsening leg swelling; and wear loose-fitting pants and shoes to avoid compressing the lower limbs and impairing blood circulation.