The human body is designed for motion. It evolved under the constant demands of movement — walking, climbing, running, building, foraging. Modern life, however, has introduced prolonged stillness, and with that comes an unintended consequence: the accumulation of stress. Physiology explains this not as coincidence, but as a biological response.

When the body is sedentary for extended periods, stress hormones like cortisol and adrenaline begin to build up. These hormones are part of the fight-or-flight system, meant to prepare the body for physical action. But when movement doesn’t follow, they linger, creating tension in muscles, elevating blood pressure, and impacting digestion, sleep, and mood. The body becomes a vessel holding stress with no outlet for release.

Muscles, particularly in the neck, shoulders, and lower back, begin to stiffen. This is partly because of poor posture during inactivity, but also because stress signals from the brain tell the body to stay alert and ready. Without movement, this alert state continues. The body prepares for action, but action never comes. Over time, this leads to chronic tension and fatigue.

Movement is the natural antidote. Physical activity triggers the release of endorphins and neurotransmitters like dopamine and serotonin, which counteract stress hormones. Deep breathing during movement also activates the parasympathetic nervous system, calming the body and returning it to balance. Even light movements — stretching, walking, or changing positions — can signal to the brain that the threat is over and the body is safe again.

Additionally, movement helps regulate blood flow and lymphatic drainage. Both systems play a key role in clearing waste and stress byproducts from the body. Without motion, circulation slows, and the physiological effects of stress become trapped.

In short, the body gathers stress when not moving because its systems expect physical action after mental alertness. When that movement doesn’t come, the stress has nowhere to go. By returning to movement, we not only stretch our limbs but signal to every system in the body: you’re safe, you can release, you can let go.