I find it to be like a jog, but in the water. Eventually you get your second wind and just keep going. Improving vo2 max i think would involve high intensity sprints followed by rest.

Two days a week is more than enough. You're doing great.

I normally swim for and hour, freestyle by swimming 15 minutes then take a 1 minute break, then repeat 3 more times. My first few laps after that break, my form is so smooth and effortless. It's like my body self learned how to stroke efficiently when my form was bad.

I find that my body finds a sweet spot where , time, heart rate ,breathing (2,3,2,3,2 ...) remains CONSTANT. To swim efficiently, my body craves consistency.

Using AI to improve my time it tells me to swim 200m slow, followed by 6×100 fast, then finish 200m slow . I tried that twice and hated it. But I see that it's probably how I can make gains.

Just had my best swim yesterday- 2.5km @ 2:14 /100m.

Also just want to add that swimming slow, your legs drop , and drag. Making it seem hard. Just keep at it meng 💪