Weak Knees and Legs, jelly legs, rubber legs, shaky legs, leg weakness anxiety symptoms

Causes

Anxiety can cause weak legs and knees in many ways, for example:

1. Anxiety-Activated Stress Response

The moment we believe we could be in danger, the body secretes stress hormones into the bloodstream, where they travel to targeted locations to bring about specific physiological, psychological, and emotional changes that enhance the body’s ability to deal with a threat – to fight or flee.

This survival reaction is often referred to as the fight or flight response [1][2][3][4].

Visit our “Stress Response” article for more information about the stress response and the many changes it causes.

The stress response causes many body-wide changes, including:

• Quickly converts the body’s energy reserves into “fuel” (blood sugar) to instantly boost energy.
• Increases heart rate, respiration, and metabolism due to the boost in energy.
• Stimulates the sympathetic nervous system, increasing nervous system activity to be more sensitive and reactive to danger.
• Heightens most of the body’s senses to be more aware of danger.
• Shunts blood to parts of the body vital to survival, such as the brain, arms, legs, muscles, and vital organs, and away from parts less essential for survival, such as the stomach, digestive system, and skin. It accomplishes this by constricting blood vessels in certain parts of the body and dilating them in others.
• Tightens muscles to make the body more resilient to injury.
• Increases perspiration to keep the body cool and expel toxins.

To name a few.

The degree of stress response is proportional to the degree of anxiety. The more anxious you are, the more dramatic the stress response changes.

Many of these changes can contribute to feeling like you have weak knees and legs. For instance:

• Sudden blood sugar fluctuations can cause weakness in the knees and legs. For instance, a sudden increase in blood sugar can lead to dehydration and electrolyte imbalances, causing weakness. An overreactive insulin response to elevated blood sugar can lead to a sudden drop in blood sugar, causing immediate weakness in the knees and legs.

• Increased blood flow to the muscles and legs can make it feel like your knees and legs have suddenly become weak.

• Increased sympathetic nervous system activity can increase awareness of your legs, making them feel weak, rubbery, stiff, unsteady, and wobbly.

• Increased sensory awareness can lead to proprioception, also called kinesthesia, which is the body’s ability to sense movement, action, and location in space, and interoception, which is the perception of sensory signals from the body. When you focus on these internal sensations, you're engaging in interoceptive attention, which can make the sensations feel more pronounced. Proprioception and interoception are common causes of feeling weak in the knees and weak, stiff, rubbery, unsteady, and wobbly legs.

• Increased muscle tension can also bring awareness to them, making them feel weak, rubbery, stiff, unsteady, trembling, and wobbly.

• Increased perspiration and respiration can cause dehydration and electrolyte imbalances, causing knee and leg weakness.

• Some people over-breathe when anxious, causing hyperventilation, and some people hold their breath when anxious, causing hypoventilation. Both hyperventilation and hypoventilation can directly and indirectly cause weak knees and legs.

Any combination of the above factors can cause weak knees and legs due to anxious behavior and an active stress response. However, the most common are sudden blood sugar fluctuations, change in blood flow, increased sympathetic nervous system activity, and muscle tension.

Acute weakness in the knees and weak legs are common symptoms associated with anxiety and an active stress response.

Anxious behavior is a common cause of acute weakness in the knees and legs. Many people notice a “weak in the knees” feeling when nervous, anxious, or afraid.

2. Hyperstimulation

When stress responses occur infrequently, the body can recover relatively quickly from the physiological, psychological, and emotional changes caused by the stress response.

However, when stress responses occur too frequently, such as from overly anxious behavior, the body doesn’t completely recover, leaving the body in a state of semi-stress-response-readiness, which we call “stress-response hyperstimulation” since stress hormones are powerful stimulants.

Hyperstimulation is also often referred to as “hyperarousal,” “HPA axis dysfunction,” or “nervous system dysregulation” [3][4][5][6][7][8].

Visit our “Hyperstimulation” article for more information about the many ways hyperstimulation can affect the body and how we feel.

Hyperstimulation can cause the changes of an active stress response even though a stress response hasn’t been activated.

Just as an active stress response can cause acute weak knees and legs, hyperstimulation can cause chronic weak knees and legs symptoms.

Chronic weak knees and legs are common symptoms of hyperstimulation.

But that’s not all. Hyperstimulation can cause this symptom in other ways. For instance, hyperstimulation can cause:

• Nervous System Excitation and Dysregulation: A chronically stimulated nervous system can act erratically and cause all kinds of nervous, sensory, circulatory, skeletal, muscular, somatic, and vestibular system symptoms, including weak knees and legs.

• Homeostatic Dysregulation: Homeostasis is the body’s ability to automatically maintain a stable internal environment despite changes in the external environment. Hyperstimulation can cause homeostatic dysregulation, leading to internal regulation problems, which can affect the nervous, sensory, circulatory, skeletal, muscular, somatic, and vestibular systems, causing muscle and sensory symptoms, such as weak knees and legs.

• Hormone changes: Hormones play a crucial role in homeostasis and many bodily functions, which can affect the various systems in the body. Since stress hormones affect other hormones, hyperstimulation can cause nervous, sensory, muscular, somatic, and vestibular system problems and symptoms, including weak knees and legs.

• Sleep disruption and fatigue: Hyperstimulation can interfere with sleep and tax the body’s energy resources harder and faster. Sleep disruption and fatigue can affect the various systems throughout the body, causing a variety of symptoms, including weak knees and legs.

• Hyperstimulation can cause chronic muscle tension, which can overwork and fatigue muscles, making them feel weak and stiff, including leg muscles.

As long as the body is hyperstimulated, it can exhibit chronic knee and leg weakness.

Hyperstimulation is a common cause of weak knees and leg symptoms.

Many anxious people worry about their health. When this symptom occurs, they worry that their weak knees and legs might be caused by a serious disease, such as Chronic Fatigue Syndrome (CFS), Muscular Sclerosis (MS), Muscular dystrophy (MD), Amyotrophic lateral sclerosis (ALS), stroke, or some other serious neurological disorder. This worry creates anxiety, which can exacerbate weakness, unsteadiness, and stiffness in the knees and legs.

Often, anxious individuals create a vicious cycle of anxiety, causing symptoms that they worry about, causing more anxiety and symptoms. This is especially true for people with health and medical sensitivities and fears.

Anxiety-caused weak knees and legs are not caused by a serious illness. Therefore, there isn’t any reason to be concerned about these symptoms. They will subside when the appropriate cause is addressed.

Other Factors

Other factors can create stress and cause anxiety-like symptoms, as well as aggravate existing anxiety symptoms, including:

• Medication
• Recreational drugs
• Stimulants
• Sleep deprivation
• Hyper and hypoventilation
• Low blood sugar
• Nutritional deficiencies
• Dehydration
• Hormone changes
• Pain

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