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Introduction/Background The aim of this study was to reveal the relation between the neurogenetic change in the nonparalytic muscles in upper and lower limbs of Polio survivors and the later muscle strength decline. Material and method Retrospective study. We looked back the data of electromyography (EMG) of Polio survivors in our Polio clinic (average age: 58.9). Muscles whose strength at EMG had been normal were extracted. We looked up the muscle strength at EMG time and two years later from medical record. Results The subjects were 23 deltoid (middle strand), 40 biceps branchii, 36 triceps branchii, 24 vastus lateralis, 19 tibialis anterior, and gastrocnemius (medial head). The ratio of neurogenic change subject (giant spike or interference pattern reduction) was, 30.4%, 25.0%, 36.1%, 62.5%, 47.4%, and 73.7%, respectively. In neurogenic change group of Biceps, 50.0% showed decline in their muscle strength. In non-neurogenic change group of Deltoid, 25.0% showed decline in their muscle strength. Conclusion Present study suggested that some muscle strength decline may be caused by Post-polio syndrome (PPS), and that EMG might be the most useful tool for the risk detection of PPS, especially for Biceps branchii. On the other hand, the fact that 25% of Deltoid non-neurogenic change group showed muscle strength decline was not understood in this study. Pain or disuse from disorder in shoulder joint might possibly be as a cause.