Swimming is not something I do a lot of. Pretty much, because I'm not a big fan. Now that I tore my ACL, it's one thing I am allowed to do ... So I am 'efforting.'
While I believe the tail of the tortoise is waaayyyy up there in the distance, I do think I'm gaining on him!
I have been trying to find leg strengthening exercises and discovered the resistance you get when you slide on a pair of fins. A lifeguard let me borrow a pair to try them out, and WOW did my legs work harder. I went faster too - which is an added bonus. No, not that fast - haven't caught up with the tortoise just yet.
I did go buy a pair of my own fins and used them today. I can't say swimming has ever made me sore, but there's a good chance my quads might feel the effects of today's workout. Dare I say, I LOVED it. I still would rather workout in a group of people - interval class, soccer, you name it. ... but this swimming thing - I might just start to enjoy it.