tand online calculator / crplot.com

The idea behind the tanda formula is that workload described as weekly mileage and average pace is predictive of marathon time.  Not yasso 800s or whatever, but just weekly mileage and pace. Kinda skeptical, but it was really close for my PR marathon.

I like that it's not only a predictor but it uses the variable that you can do something about.  What do you do to run faster yasso 800s?  A lot of people would say run more 800s, but the answer is mileage.  I also found that during my best year, I didn't do a bunch of intervals, but just ran some steadier paces rather than super easy + workouts.

Looking back at some logs with the tanda calculator in mind I can see where things went south.  Even when I ran OK mileage of ~50/wk in Sept 2014 I was doing it super slow -- 11:15/mile -- because I was just trying to run easy mileage and not worried about PRs.  I was surprised I only ran 1:18 at a 10 miler Oct 14, but that's well ahead of the tanda prediction.  40h11m and 213.9 miles Sept 2014 equals 11:16 pace.  Plugging in tanda gives 3:58 marathon and 1:25:44 for 10 miles.  People use an offset for shorter distances, but I also think I coasted on residual fitness for a number of years.

Now

Here's where I am now.  Predicts a marathon of 4:28. I think that's generous, but not crazy.

I love this graph because it says what to do.  Move right or move up.  Do either slowly of course.  I plan to move right with miles and move up with lost weight -- a virtuous circle.  When I'm out of time in the week, maybe I move up with a little more effort.

Then

Here's where I was when I ran my BQ.  This is remarkably accurate.  I averaged 8:54 pace that year and think it's pretty close to my average in the lead up. And I was doing about 70 miles/wk or 16k per day before the marathon.  5:32/km is 8:54/mile.

Future?

Now, it's hard to imagine my blue dot taking a sharp left up the graph, but I guess I can see it floating up as I lose weight.  The dream goal is to get to 3:35 by Fall 2025, so I can qualify for Boston 2027 as a M55.  Unless I tire of this silliness before then :-)  At 16km/wk, this suggests an average pace of 6:11/km or 9:57/mi is required.  70 mpw doing 10-minute miles doesn't seem crazy... says the guy doing 35mpw at 12:30+