Over half of the healthy population exhibits leg shaking, a repetitive and rhythmic movement of the legs while seated. Some brush it off as just a habit, but most of the time, there’s a reason for it, ranging from anxiety to medications. Usually, it is not a cause for concern, but if it is disrupting your daily life or is accompanied by other symptoms, it is best to seek medical advice. Here are some causes of leg shaking:
The “fight-or-flight” response: You may have noticed someone shaking their legs while studying for a difficult upcoming exam. Or maybe that someone is you. During such times, your heart pumps out extra blood to your muscles, readying them to run or engage. As a result, your legs start shaking. This happens when you are in “fight-or-flight” mode, and adrenaline is released in your body as a response to something scary (in this case, the exam). For people with anxiety, even non-threatening situations can trigger this response, which is sometimes accompanied by other symptoms like a pounding heart, nausea, and unsteady breathing.
Concentration: When you are working on something you love, you are giving almost your full attention to it. When you are concentrating on doing something, your legs may start shaking. And that’s a good thing, because it helps you focus! It is especially useful for people with attention deficit hyperactive disorder (ADHD), a condition that causes a hard time paying attention, being hyperactive, and being impulsive, as leg shaking improves concentration and attention.
Boredom: You may have experienced leg shaking when you are bored, like when you are waiting for something with nothing to do to pass the time. Boredom is uncomfortable, so to release that tension, your legs start to shake.
Medications: Many medicines may cause leg shaking as a side effect. These include medications for mental health conditions and allergies.
Parkinson’s Disease: Parkinson’s is a condition that affects the nervous system. It is caused by damage to nerve cells that produce the chemical dopamine. Dopamine normally keeps movements smooth and coordinated. People who develop Parkinson’s disease experience uncontrollable movements that progressively worsen over time. Shaking in the hands, arms, legs, or head is one common symptom of Parkinson’s disease. Other symptoms include muscle stiffness or rigidity in the arms and legs, slow movements, and the loss of reflexes and balance.
Restless leg syndrome (RLS): It is important to know that RLS is different from simple leg shaking. RLS is an uncontrollable urge to voluntarily move your legs due to tingling, burning, or pain. Simple leg shaking does not include these sensations and is mainly involuntary. Symptoms of RLS improve with movement and typically worsen at night.
Additionally, research suggests that leg shaking could also be a form of exercise for people who have to spend long hours sitting in one place. Obesity and related chronic diseases are linked with low physical activity, and leg shaking provides a simple and feasible approach to get some physical activity in for people who are too busy or unable to go for a walk.
