Long and an Inactive Calf Pump
The calf muscles help push blood upward from the legs toward the heart. This is why they are sometimes called a “second heart.” The source article explains that when calf muscles stay inactive for long periods, blood can pool in the lower legs and contribute to swelling, fatigue and varicose veins.
Long hours at a desk, driving or sitting on the couch can make legs feel heavy and stiff. Small movement breaks can help.
Try standing up every hour, walking for a few minutes,