My right calf muscle when stretched becomes a very hard knot. It resists any treatment I have tried. A famous acupuncturist here in Japan said that it is fat that has hardened around the muscle possibly because of a knee injury that I had 35 years ago which still bothers me a bit. At that time the doctor said that it was a sprained knee but tests could find no lasting damage. I discovered this knotted muscle about three years ago when I noticed a new type of pain in my leg sometimes and particularly from certain movements that I did when I was teaching an Aikido class. Do you have any idea about what this might be? I am 61, active and in good shape. I am now about 5 feet 9 and weigh about 68 Kilos.