In 1846 Whitman wrote:
In our sundown perambulations of late through the outer parts of Brooklyn, we have observed several parties of youngsters playing “base,” a certain game of ball.
…
The game of ball is glorious—so are leaping, running, and wrestling. To any person having the least knowledge of physiology, it were superfluous to enter into any argument to prove the use and benefit of exercise. We have far too little of it in this country, among the “genteel” classes. Both women and men should be careful to pass no day of their lives without a portion of outdoor exercise.
America: fat even in 1846.