Leg pain after a recent viral illness occurs frequently because of post-viral inflammation, muscle weakness, dehydration, fatigue, vitamin deficiency, or transient nerve and muscle irritation during recovery. The pain may feel like heaviness, cramps, soreness, weakness, or body ache and can continue for days or sometimes weeks after the fever or infection improves. Relief may improve with adequate rest, hydration, proper sleep, and gradual return to physical activity. Pain-relieving medicines such as Paracetamol are commonly used for temporary relief depending on your medical condition. Warm compresses, gentle stretching, light walking, and protein-rich, nutritious meals may also help improve muscle recovery gradually. Doctors sometimes evaluate vitamin D, vitamin B12, calcium, or electrolyte levels if leg pain and weakness continue after a viral illness. Avoid excessive exercise or heavy physical strain until your strength improves. Seek medical care if leg swelling, redness, severe weakness, breathing difficulty, numbness, chest pain, or difficulty walking develops, because persistent or severe leg pain after infection may require further medical evaluation.