All fall I swam usually 2 to 3 days per week, about 2000 yd per workout, and did perhaps 2 days a week on some weight machines. In addition I walk fast several times a week, do occasional bicycling, and some hiking. During the previous 4 years I worked out with the local age group and/or high school swim team, which did a lot to increase my endurance and technique. Without the team workouts, I'd never have made myself learn to do even a rudimentary butterfly or a decent backstroke flip turn.
Before that I swam alone for many years, although I swam a few summers with a masters team in Knoxville, 60 mi away. I've been in a few swim meets. Freestyle and breaststroke are my best strokes.