I’m a 58 y.o. competing against men 20 years younger in our triathlon group. Is there a valid formula or method to compare results in triathlon events, especially 1/2 and full IMs that has a age component. I’m thinking of percent of age group vs age group winner. Any Opinions? Thank you in advance.
No HTFU!
ps. Hey, it’s slowtwitch, you had to expect this. 
pps. I’d actually be interested if people could compare their own 58 vs 38 type results, complete with thoughts.
They do this with the USAT rankings, I think. There is a formula, I believe, that you could use to compare yourself to other age groups.
Since the other poster got the HTFU out of the way.
The empirical way to do it is go look at the results for some applicable major race, say Kona. Calculate the average time for the top X finishers in each age group. From those averages you can calculate the percentage difference. Say the average 35-39 time is 10:00 and the average 55-59 time is 11:00, than the difference is…10%, etc. So you can then take your time and multiply by 0.9 to get something approximating a time normalized to the 35-39 age group.
Don’t look at age group winners. They’re outliers. You don’t don’t want Joe Bonness totally jacking up the calculation.
Take a cross section of high-level competitive races and compute the % difference between 35-39ag and the 55-59ag, maybe average the top three or five in each to smooth the data a little. I’m willing to bet that you will get a reasonable fasimile.