The calf of my legs are very sore and weak. Hurts really bad when I walk. My doctor change my blood pressure med to VALSARTAN 80 MG. a few days prior to me flying out to Las Vegas for the Christmas Holidays I was flying for 4 hrs. I got a really bad cramp in my left leg while on the plane. I stood up and walked up and down the aisle. Since arriving in Las Vegas, I have been doing lots of walking around the 5th day of being here, I began experiencing very sore and weak calves. Can you please tell me what I can do. I am scheduled to fly back home on tomorrow on a 4 hr flight. I am a 65yr old black female. My overall health is good. I do take vitamins and supplements.