I am a very healthy, active 53 year old female. I am off work for vacation, but stayed at home. This past week I had low energy and a bit of a cold . Yesterday I felt much better, but the night before I had difficulty sleeping because my left thigh area has been aching. The muscle isn t tightning, but it hurts. Yesterday I asked some friends about it and was told that I might be dehydrated. So I started drinking more water and also got some tonic water. I felt better, but then in the middle of the night had the same thing going on again.