Nowadays I try to swim races as a "work of art" and seek satisfaction based more on my success in doing so than based on time or place. Admittedly the former is a subjective judgment, while the latter is objective, but that just means I have to be more creative and flexible in my assessment.
When measuring swimming by time, choose a current time as your benchmark.
Measure results empirically. Those who excel in many disciplines set up meaningful feedback loops so they can objectively and accurately evaluate the link between efforts and outcomes. After swimming that "slow" time in December, I immediately made it the benchmark by which I would measure improvement in the three to five months (Masters short course season) to follow, and began making constructive plans to improve it.
I also begin most practice sessions by doing an assessment swim or set. The data points I use to measure it always include strokes per length (SPL) and/or tempo in addition to time. The practice then becomes an exercise in achieving measurable—and smart—improvement. And when I do achieve improvement, I leave the pool with a feeling of accomplishment that provides the motivation to do it again and again and again.
Focus on the quality of time, not the amount.
A corollary of the fact that races are likely to last longer at 60 than they did at 40, is the possibility that practice sessions will be shorter. In either case, you should strive to make those minutes or hours the best they can be.
I last broke 19 minutes for 1650 yards (equivalent of 1500m) in 1992. I last broke 20 minutes in 2006. But these days it's a challenge to break 23 minutes, a pretty rapid decline for only six years. So my goal is to make a 23-minute mile feel better and more satisfying than a 19-minute mile did 20 years ago.
As I've aged, I've also been unable to swim as long in pool practices. As a result of arthritic narrowing in my lower spine, my calves and feet experience 'terminal cramping' after a diminishing number of push-offs. Where I was able to swim a 10,000-yard practice (while training for the Manhattan Island Marathon) at age 51, I could manage only 5000 yards at age 55. At 60, I can often barely make it to 3000 yards before I simply can't push off any more.
Rather than get discouraged, I've embraced the challenge of making every lap count, starting with the very first. This has given each practice a stronger sense of purpose than ever before.
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