|Diana Nyad, then and now|
She swam non-stop for 53 hours from Cuba to Florida, thus achieving at the age of 64 the dream she'd had since she was twenty. Amazing! And remember, this is a dream that champion swimmers have had for the past 75 years without anyone ever achieving it.
Here's her TED talk about it (done in December), enjoy it!
She's right: Never, ever give up! This applies not only to sports, but to everything in life.