A place for runners.
My race predictor said I should be able to do a 19 minute 5k. To test this out I did a 5k on the weekend and went out around 4 minute kilometer pace and definitely couldnt keep it up after the first 2kms. Finished in 21:18 which is still a nice PB but nowhere near 19 minutes.
I'm going to try guage my performance based on training runs from now on. I could do 5/6 1km reps at around 4:15 per km which seems to correlate with what I did during the race.
I feel that they slightly overestimate for me. Although, I'm never quite sure if the prediction is for perfect conditions on a flat route.
Another thing to keep in mind is that watches uses track further distance then the actual course. My fastest official (parkrun) 5k time is around 22:10. Garmin logged the 5k time as 21:xx as it had tracked around 5.1km. This was closer to my Garmin prediction of 21:45
I've found the estimated times to be almost laughably bad, and worse the longer the distance.
Right now, mine estimates:
My 5k PB is 18:48, 10k is 38:55, and I've only done one marathon at 3:14:24. But right now? My goal is to do a sub-18 5k by the end of the year, and that is far from a sure thing. I've no hope of doing it today, and I doubt I could even complete a marathon (at least in any remotely reasonable time) today.
So no, I don't put a lot of stock in it.
My talent lies more in the longer distance when I compare myself to my running mates. And this is also reflected in my Garmin race predictor. My 5k is estimated too fast (16.25 vs 17.00), and my 10k (35.30 vs 34.30) and up is estimated too slow. But I also put more effort in improving the longer distance. On average I think it works pretty well, but I find the trends more valuable than actual numbers.