Many people have the habit of sticking one foot out of the bed while falling asleep. Though it may feel like just a quirky personal preference, research shows there’s a physiological reason behind it. As you prepare for sleep, your body begins to cool down, and exposing an extremity like a foot helps dissipate heat more rapidly. The feet, along with hands, are highly effective at releasing heat thanks to specialized blood vessels called arteriovenous anastomoses, which allow more blood to reach the skin and thus enable heat loss.

Temperature regulation is a key factor in achieving restful sleep. To fall asleep and stay asleep, the core body temperature must drop slightly—a mechanism that signals the brain that it’s time to rest. When one foot is uncovered, it acts as a mini radiator allowing heat to escape, helping the body reach that slightly lower optimal temperature needed for deeper and more stable sleep.

But the blanket trick is just one part of a broader approach to sleep hygiene. Creating a calm, cool environment (often recommended around 60-67°F or 15-19°C) and maintaining a regular sleep schedule, avoiding heavy meals or screens before bed, and limiting long daytime naps can further improve sleep quality. The idea is that small habits can add up—so combining instinctive moves like exposing a foot with consistent routines supports better rest.