Nudity
Male nudity

Historically, men and boys bathed and swam nude in secluded rivers and lakes. In England when sea bathing became popular in the 18th century, beaches were initially male only, but with the easier access of the 19th century due to rail transportation, the mixing of genders became a problem for authorities. The addition of " bathing machines " at seaside resorts was not successful in maintaining standards of decency, men often continuing to be nude while women wore bathing costumes. However, public concern was only regarding adults, it being generally accepted that boys at English beaches would be nude. This prompted complaints by visiting Americans, but Englishmen had no objection to their daughters being fully dressed on the beach with naked boys.

In the United States and other Western countries for much of the 20th century, male nudity was the norm in gender segregated activities including summer camps, swimming pools and communal showers based on cultural beliefs that females need more privacy than males. Beginning in 1900, businessmen swam nude at private athletic clubs in New York City, which ended with a 1980 law requiring the admission of women. For younger boys, lack of modesty might include public behavior as in 1909 when The New York Times reported that at an elementary school public swimming competition the youngest boys competed in the nude.

Hygiene was given as the reason for official guidelines requiring nudity in indoor pools used only by men. Swimmers were also required to take nude showers with soap prior to entering the pool, in order to eliminate contaminants and inspect swimmers to prohibit use by those with signs of disease. During women's weekly swim hours, simple one-piece suits were allowed and sometimes supplied by the facility to insure hygiene; towels were also supplied.

Compared to the acceptance of boys being nude, an instance in 1947 where girls were given the same option lasted only six weeks in Highland Park, Michigan before a protest by mothers. However, only the middle school required suits, the elementary schools in the same district continued to allow girls to swim nude. The public health recommendation of male nudity continued officially until 1962 but was observed into the 1970s by the YMCA and schools with gender segregated classes. The era of male nude swimming in indoor pools declined steadily as mixed-gender usage became the norm, and sped up following the passage of Title IX of the Education Amendments of 1972. Eventually all pools use became mixed-gender, and in the 21st century, the practice of male nude swimming is largely forgotten, or denied as having ever existed.
combination:repeat_prompt