What causes pain and weakness in both legs?

Bilateral leg pain and weakness can stem from various causes, including nutritional deficiencies, lumbar spine disorders, hypertension, and other conditions. Nutritional deficiencies—such as insufficient calcium, zinc, or potassium—can readily lead to muscle pain and bilateral leg weakness. Lumbar spine disorders (e.g., lumbar disc herniation) may irritate spinal nerve roots, resulting in leg weakness and pain. Additionally, impaired flow of Qi and blood can hinder normal circulation, leading to muscle soreness and weakness.