This pool practice from Week 2 of my marathon training program illustrates the value of collecting the data that matters from your swims.

Wed Feb 10 0800 AM at Coronado Pool        3500 LCM

Set #1 7 x 400 on 7:30 – “Tempo Pyramid”

Time, Tempo and Total Strokes

Notes: This was another example of what is becoming a favorite set – a “Tempo Pyramid” in which I (i) start with a faster tempo; (ii) slow tempo gradually, seeking to reduce SPL; then (iii) speed tempo again, intent upon minimizing SPL increase. As the chart shows, I took off 28 strokes, from #1 to #4 as tempo slowed. From #4 to #7, as tempo increased again, I added back only 9.

I calculated stroke count for each 400 by dividing time by tempo then subtracting 24 (I allow 3 beeps on the initial pushoff and all turns.)  My last 400 was 21 seconds faster than the first – though both were at the same tempo — because I took 19 fewer 1.1-second strokes.  (This improvement – multiplied by the approx 95 x 400 in an English Channel swim – converts into reaching France 32 minutes faster, in about 1800 fewer strokes.)

Most people know only one way to swim faster – stroke faster and work harder. By using the Tempo Trainer (combined with hundreds of hours of technique practice) I’ve learned to swim faster by traveling farther. The Tempo Pyramid has proven to be one of the most reliable ways to imprint that on my brain.

Experience has shown me that slowing my tempo (by precise amounts as the TT allows) dependably leads to a longer stroke. Not by accident but because I use the extra time to improve my streamline and stroke. A good outcome is when I stroke slower and swim the same time. A better outcome is when I stroke slower and swim faster, as I did here.

When I begin increasing tempo again, on the 2^nd half of the set, I concentrate on making it feel slow. Indeed the last 400 felt more leisurely than the first. I felt as if I had more time between beeps to extend my bodyline, trap water behind my hand, etc. Taking 19 fewer strokes shows that perception indeed had become reality.

This is also an illustration of how rapidly the brain and nervous system adapt when you give them the right kind of stimulus. Adaptation here was stimulated by (i) the intense focus I gave to each stroke; and (ii) the auditory stimulus from the Tempo Trainer beep. The nervous system adapts far faster than the aerobic system – and when it does adapt you sense it immediately. That’s motivating.

Set #2 8 x 50 @ 1.10 and 36 SPL, resting 10 beeps (11 sec.) at each wall.

Notes: I finished practice with a brisk set of 50s. I do these in hopes of improving Set #1 when I repeat it in the future. Finishing 50m in 36 SPL at a tempo of 1.1 (allowing 3 beeps for pushoff) gives a time of 42.9 sec, or a pace of 5:43 for 400. This set starts developing a neural program for traveling farther and faster in 1.1 sec than I did on the 400 (39 strokes per 50 and a pace of about 47 sec.). The more 50 repeats I swim with fewer strokes and seconds, the more robust that brain circuit becomes. Eventually, I hope, it will be strong enough to sustain that pace for a nonstop 400, during a set such as today’s.

Endnote: A comment described me as having a preference for scientific training. It’s more accurate to say I prefer empirical training. I train in ways that provide measurable feedback that allows me to link efforts to outcomes. I.E. That a particular combination of SPL and tempo allows me to hold a stronger pace at a more sustainable effort level. That tells me where to focus my training efforts. At age 59, training for 3 marathons, I don’t want to waste energy and time on ineffective – or unexamined – training.

Evening Swim – 2 Miles in the 57F Pacific along Coronado’s Silver Strand. I swam right along the breaker line for a bit more fun and challenge.