Leg pain for seemingly no cause.

Legpain as in your case is commonly due to muscle cramps which results from 1.Dehydration, 2.calcium deficiency or conditions like 3. Atherosclerosis of blood vessels,  4.Thyroid or kidney problems. Considering your age its most likely due to dehydration or nutrition related. It will be relieved by simple measures as follows: Take adequate liquids, sports drink like Gatorade,  fruit juices , buttermilk,  lemonade etc. 2. Stretch your calf muscles daily. 3. You can massage calf muscles and apply cold pack when they pain. In cases of severe pain take simple analgesics like paracetamol. 4. Avoid prolonged standing or sitting cross-legged. Change postures in between. 5. Take calcium supplements. 6. Take healthy nutritious diet. 7. If you are taking medicines like diuretics,  statins, review with your doctor as they can cause cramps too. If problem persists get your thyroid profile, kidney functions  done and consult with your doctor.