You can ask the Library of Congress. The LOC Everyday Mysteries service has a page devoted to the question about the strongest human muscle, explaining for starters that there is no one answer because there are three different ways to measure strength. That said, three different types of muscles are described for the human body: cardiac, smooth, and skeletal.
With lots of illustrations, the question about the strength of muscles in the human body is answered in interesting detail, in an excellent article packed with information and insight. At the end there are links to related websites chosen by the librarians, and a list they have selected for further reading.
Trusting the Library of Congress to authenticate information
The Everyday Mysteries service of the Library of Congress is an example of an internet source that can be fully trusted for student research. Not only are essays and illustrations provided. The librarian recommended web sites expand into a network of authenticated knowledge about human muscles — and for the many other subjects of the Everyday Mysteries.
