This guide book is for horse folks interested in or studying diseases and disorders of horse health. In it you will find exercises to familiarize yourself with the terminology used to include a word search and glossary. There are bulleted lists for ease of reading, a study guide and a quiz for self evaluation of the understanding of this metabolic disorder. Tying-up and Azoturia are referred to as Exertional Rhabdomyolysis. It is the most common muscle problem in horses and surfaces as being either being sporadic or chronic. The genetically inherited chronic forms are Polysaccharide Storage Myopathy or Recurrent Exertional Rhabdomyolysis. If a horse displays symptoms immediately stop from working and call the veterinarian. Signs include reluctance to move, profuse sweating, and hard muscles in the hindquarters. There are many possible causes. An excessive amount of glycogen stored in the skeletal muscles from high grain diets being continually fed on days off or a genetic predisposition to store extra glycogen may disrupt the metabolic energy development once work is reestablished. A genetic abnormality causing muscle contractions could also be the culprit. Proper diagnosis and treatment protocol will be based individually. Typically a change in diet and continual exercise with turn-out will eliminate or reduce Chronic Exertional Rhabdomyolysis. A well followed conditioning and feeding program could prevent an attack. This would include reducing the sugar and starches on days off. This guide will provide you: *An introduction to equine metabolic disorders *Names and forms associated with Tying-Up and Azoturia *Anatomical systems involved with exertional rhabdomyolysis *Possible symptoms of a horse that is Tying-Up or developing Azoturia *An introduction to carbohydrates and normal energy processes *Cause and process of the disorder exertional rhabdomyolysis *Immediate handler care essential to be given to a horse displaying symptoms *Diagnoses of exertional rhabdomyolysis *Possible veterinary treatment *Prognosis of horses with *Recovering from *Maintenance of horse that has episodes *Disease spread *Preventive measures to reduce the likeliness of Tying-Up and Azoturia *Historical theories behind the cause and treatment