A final part of this treatment required vigorous physical exercise to help the body force out the disease via perspiration. This last concept particularly appealed to 19th century American women, who normally were forbidden such strenuous physical activities because of their supposed physical frailty. Hydropathy reached its peak of public support in the 1850's, yet continued in dwindling numbers into the early 20th century. I believe we can directly correlate Priessnitz's theories with the more current health crazes for hot tubs, fitness spas, and running.