I can't either at 64 year old. The most yardage that I have done in workouts is 2,000 this year. Usually between 800 to 1600 yards. I like doing all four strokes and not all freestyle. Probably, breaststroke the most since I like kicking breastbone on the board. Unlike Michael Andrew going 15 seconds on each 25 yard is too hard for me as well. I do 25 yards at 30 to 1 minute rest. In fact the workouts sometimes they give I couldn't do in my 40's either when I still did a 1:34 100 yard breaststroke. I have swim one 200 yard fly at 4:50 in workouts.