Some students of the artist and photographer Thomas Eakins, perhaps posing for a study to be used in one of his paintings. This photo was taken in the 1880's, and the nude wrestlers would have had to hold that pose for several seconds to allow for enough exposure time. Note the blurred clothed figure in the background.

 

The artist Thomas Eakins (1844-1916) on the left with fellow artist John Laurie Wallace (1864 - 1953) in 1883.

 

Thomas Eakins - Two male nudes about 1884.