We produce ZH-YLS-4C switch rod fatigue tester is similar foreign products and the "pharmacological experiments methodology" scotch test apparatus according to improvements completed, a better experimental, anti-fatigue detection screening and identification of an ideal drug instruments. The instrument can do fatigue experiments, skeletal muscle relaxation experiments, CNS inhibition experiments, as well as other required test to detect movement of drug action, such as to affect the toxicity of athletic ability, the lack of impact on the athletic ability of a substance the body, mind cerebral vascular drugs on athletic ability and so on. The instrument can be developed using the basic principles and the basic functions of the multi-directional