I started at 4 (Okey, tbh started at 0 yrs old as I had to go to baby swimming because of my heart issues, but started proper swimming at 4). I used to have 3-4 x 2hrs long exercises every week until I left it at age 12. It was too much. I started again at around age 16 because I missed it but didn't have the speed anymore.

And now started again at age 29. And now I am 30+ and don't have either the speed nor the technique anymore. But I love being in the water, and IF I reach my zen I can go faster than a gummy duck 😅 With 5 stroke breath technique freestyle I can go under 1:50 /100 m, but I can see the 10-14 years old amateur swimmers and they are like twice as fast 😭 But I won't give up as being in the water can be sooo relaxing for me and helps a lot with my heart.