Like sparrow said, swimming is a totally different animal!
When I started, I could only do 2 laps without an 8 breath rest (I was in very bad shape and overweight), but the improvement you will see can be amazing if you keep at it. My biggest problem now is having enough time to swim as much as I really want to.
I'm doing full laps at 50 seconds per lap, and swimming non-stop for 45 minutes until I just have to get out due to time or one of the elderly peoples classes begin. And I am a poor endurance runner.
I don't know the jargon when it comes to breathing, but I breathe on every third stroke, so every breath is on the opposite side from the previous. For me, it seems to help keep my form consistent.
I just wish there was some easy way to count laps...it is very easy to lose count and get off by at least one lap per ten, then I don't know what my pace is anymore...not a big deal, but it's the way to keep tabs on progress.
FWIW, there are 2 older ladies (I am 40) and 2 older guys, and by that I mean around 50-55, that absolutely blow me out of the water, and for just as long. Only one of them wears those webbed gloves.
Now if I could just master a flip turn without forcing water up my sinuses, everything would be sweet.
Great results in your training gr8! I know what it's like to go through the plumbing fixes, at least to a degree. My cardiologist did an angiogram, expecting to install a stent, but he decided after looking at the bad pipe that I need to change my ways, or it will just get plaqued over, so he came back out without doing anything. Since then, I've been doing about what you are doing, with similar results.
What are your blood lipids doing?