Rush of muscle fatigue

On several occasions I have had a rush of muscle fatigue. It has been from the waist up or it could be from waist down. I happens rather quickly. I feel as if the muscles are escalating in fatigue and reaches a point where it seems I can't tolerate it then it will just subside and leave me exhausted. Today it happened as I was walking my dog. I opened my back gate to enter. From my belt line to my feet went into an escalating muscle fatigue almost to a painful cramp then it subside. I literally could hardly pick my legs up to walk. I felt as if I was gonna collapse. When it began to ease off. It took about 10 minutes to recover.
Any suggestions as to what it is.?
Judge51

[Dr Sharma]

Hi there. You need to consult a neurologist for assessment of these symptoms since you could be suffering from fibromyalgia or chronic fatigue syndrome. Other symptoms are irritable bowel syndrome, memory difficulties, numbness and tingling in hands and feet, palpitations, tension or migraine headaches. Treatment would include physical therapy, anti depressants and muscle relaxants, cognitive behavioral therapy etc. drugs approved are duloxetine, pregabalin etc. Take care.