Seventeen laps in, I'm not getting tired.
850m of swimming is not far, but it's far for me. Last time I did this, I struggled with 60m.
The previous day, a dancer described me as "a really good lead".
Now, this was definitely cheating: this was a beginner workshop, and I've been swingdancing, on-and-off, for five years. But the last year has been off, and I've forgotten everything. While I will, as I'd feared, have to learn everything again, I'll be ready for the social floor in weeks, not months, this time.
I've understood for a while that capability is a sawtooth: gradual gains offset by sudden falls. What I hadn't realised is that the slope of the saw increases. While we must begin again, each time we do, we progress faster.
Sooner than I might otherwise have expected.