How accurate is the race predictor?

Unfortunately for most people it's a tad ambitious. My half time is shows as 7 minutes inside my PB. Run on feel and don't go out too quickly,

CW

Use the numbers to guide what you do, not dictate what you do. Ask yourself, can you run at 5:41/km (9:10/mi) for 2 hours?

Any of the performance or recovery metrics are informational only, not instructional. You still have to use the top 100mm to process the information and use it to your best advantage.

+1 on above. For many the estimated times are very aggressive, the longer the distance the more aggressive they are.

What many have reported and what is true for me is that the times for the HM and FM are similar to a VO2 two points lower than you have, so say your score is 50, look at the projected race times of 48 and they might be more realistic.

You can google the scores and race times.

Not at all accurate. it has me 3 minutes faster than my PR for a 5K. The race predictor, plus the unusual recovery time estimates, make me wonder if anything else is accurate.

As I have gotten fitter over the past two years the predictor has gotten much more accurate.

Just out of curiousity: does the race predictor factor in the altitude? What I mean is, where I run it's almost never flat, way too many small hills. So I could never match the times my race predictor is telling me on my usual route. But maybe the times are a bit more realistic when I would run on a flat terrain (meaning, whitout the extra extortion of climbing those darned hills)?

First event tomorrow. Half-marathon. Just curious. It reckons I can do a sub 2 hour (by about 20 seconds lol) but I think that's beyond me. Previous half-marathon (non event, just me on my own) was a year ago and 2:20 (recorded on Fitbit). Dare I hope...

Sooooooo ... I'm curious, how did your race time match up with the predictor?

Max

Just out of curiousity: does the race predictor factor in the altitude? What I mean is, where I run it's almost never flat, way too many small hills. So I could never match the times my race predictor is telling me on my usual route. But maybe the times are a bit more realistic when I would run on a flat terrain (meaning, whitout the extra extortion of climbing those darned hills)?

I dont see how it can. The 235 doesn't have an altimeter, and GPS altitude is pretty ropey.
It gets corrected in garmin connect with map/elevation data.
But your VO2 max get calculated instantly on the watch before it even gets there.

I dont see how it can. The 235 doesn't have an altimeter, and GPS altitude is pretty ropey.
It gets corrected in garmin connect with map/elevation data.
But your VO2 max get calculated instantly on the watch before it even gets there.

Yeah, I didn't think of that, thx.

It's funny though. Because of health reasons (and the subsequent lack of Training) my VO[SUB]2[/SUB]Max dropped from 57 to 49 (Polar) resp 42 (Garmin). But my Race Predictor is way to optimistic when factoring in this massive drop in VO[SUB]2[/SUB]Max.

As much as I'd like to call it overly ambitious, I think it is scarily accurate.

I think that I get in my head on races a lot, and don't push myself as hard as I possibly could go. I never bonk at a race, and in fact usually have plenty of gas in the tank at the end. Also, I don't use nutrition as smartly as I should. I look at those numbers as "If I planned as perfectly as possible this race, this is the number I could achieve."

That said, none of the estimates are lunacy IMO. I've never done a sub 4 hour full marathon, but I intuitively know I could (considering how I felt after my last one, which was almost too good, LOL), and Garmin's race predictor says I could. Now the question is, do I want to put in the work and planning it would take to get there....