This paper mainly discusses the confusion and unification between elderly people's physical activity and aged physical activity with the methods of documentary and analysis.The confusion between two concepts means the selective usage and mixed usage from journal,essay author and research contents,which causes some problems in academic principles,academic duty,reference citations and information retrieval for related research field.Compared to the concept of aged physical activity,the concept of elderly people's physical activity has more support in theory,laws and policy field,which means it i...