The Fluid Reservoir in Your Lower Legs
To understand why your legs are disturbing your sleep, we need to examine how fluid moves when you're not paying attention. Throughout your day—whether you're working hard at the office or running errands—fluid can accumulate in the tissues of your legs, a condition known as peripheral edema. It's not always visible swelling; sometimes it's just enough to leave a slight indentation from your socks at day's end. This "third-space" fluid remains trapped in your lower body as long as you're upright, but the moment you lie down, everything changes.