800 PR = 400 PR + average 400 pace during 1500 PR?

This formula is accurate for me.

by that math Blaziers pr would be 1:44.58 instead of the 1:42.34 it is.

It works for me. It's within a second.

This is actually a good formula. I ran 3 seconds faster and some change for my 800 or than the formula suggests. But I also could've ran the 1500m much faster than my pr is

Seems ok for a ballpark idea, maybe not a very precise predictor. Esp for speed-based 800m guys who have a faster 400m compared to their 1500 fitness.

Of course, it’s implicitly saying that your 800 pace is approximately the average of your 400 and 1500 paces. But if you really want to get technical,

(1) pace increases (deteriorates) roughly logarithmically with distance, i.e., doubling the distance beyond 1500m or so deteriorates pace by roughly the same percentage (this part being approximately consistent with the formula ignoring the 1500/1600 distinction);

(2) 800 is the greatest exception in that for most runners, there is a 15-20% pace slowdown in going from 400 to 800, but nowhere as high a slowdown in doubling at pretty much any other distance, both lower sprint distances and higher distance distances.

The 800 is the point of transition from sprint to distance (not 400) because it’s the longest race that’s almost always won with a positive split, so it figures that it’s somewhat of an anomaly.

Sub-8 Mile wrote:

Seems ok for a ballpark idea, maybe not a very precise predictor. Esp for speed-based 800m guys who have a faster 400m compared to their 1500 fitness.

I'm speed-based, and it predicts my time down to the tenth.

400 PR = 56.1

1500 PR = 4:41.6 = 75.1" per lap

Predicted 800 PR = Actual 800 PR = 56.1 + 75.1 = 2:11.2

pikacho wrote:

by that math Blaziers pr would be 1:44.58 instead of the 1:42.34 it is.

Jakko Ingebrigtsen is ahead of the curve (51.03/56.48) ... 1:47.51 est (1:46.44 actual)

In my prime:

50 + 1:09 = 1:59, 800 was 2:00

I'd say this is spot on, as I did not have the opportunity to run a fresh mile for either my junior or senior years of HS.

Currently:

55 + 1:11 = 2:06, 800 is 2:08

Fine calling this accurate as well, as the 2:08 is the most outdated PR there and I could probably run at least 2:07.

Not bad.

Surprisingly accurate formula.

400 PR (51.2) + 400 Pace/Mile (67.1) = 1:58.3

Actual PR: 1:57.92

runne wrote:

The 800 is the point of transition from sprint to distance (not 400) because it’s the longest race that’s almost always won with a positive split, so it figures that it’s somewhat of an anomaly.

The 400 and the 800 are the weird events. The short sprints (60, 100, 200) are also typically won with negative splits, just like the 1500 and up.

Bolt's 200m WR had 100 splits of 9.92 and 9.27. Even if you don't take reaction time into consideration, that's still a pretty significant negative split.

Formula works for many 800m/1500m athletes. Formula is going to be consistently inaccurate for elite 400m/800m men such as F.A.T. sub-46 400m guys with slower than 3:45 1500m.

Spartacus van der Bahn wrote:

pikacho wrote:

by that math Blaziers pr would be 1:44.58 instead of the 1:42.34 it is.

Jakko Ingebrigtsen is ahead of the curve (51.03/56.48) ... 1:47.51 est (1:46.44 actual)

I think he could go faster than 51

acceleration matters wrote:

runne wrote:

The 800 is the point of transition from sprint to distance (not 400) because it’s the longest race that’s almost always won with a positive split, so it figures that it’s somewhat of an anomaly.

The 400 and the 800 are the weird events. The short sprints (60, 100, 200) are also typically won with negative splits, just like the 1500 and up.

Bolt's 200m WR had 100 splits of 9.92 and 9.27. Even if you don't take reaction time into consideration, that's still a pretty significant negative split.

Good point, but sprints are technically negative splits only because of the slower acceleration phase from the start. If you look at speed starting from the point where they’ve accelerated to cruising speed — typically within the first ~50m — all races up to 800 almost always involve decreasing speeds over time. Almost no one tries to strategically win these races by saving the kick for the end, rather you just run as you hard as you can upfront so as to not have to slow down too much towards the end.

“Almost” because the longest standing 800m WR was negative split by Jarmila Kratochvilova: 56.82 s and 56.46 s respectively. She just kept on accelerating till the end, her last 4x100m splits being: 14.6, 14.1, 14.0, 13.8 s. Source: @5:05 in the TRP video below.

400: 50.X

1500: 61 (3:47)

Hypothetical 800: 1:51/2

Real 800: 1:53.7

Makes sense for me, always felt like my 800 wasn’t as good as I could run. My goals this season are to run under 1:51 and 3:45 so that would still line up well in this formula

Seppo Kaitenenn wrote:

Spartacus van der Bahn wrote:

Jakko Ingebrigtsen is ahead of the curve (51.03/56.48) ... 1:47.51 est (1:46.44 actual)

I think he could go faster than 51

he can probably go faster than 51. AND his best 1500 pace is actually closer to 55.5 i think

49.63

3:55.9

Avg = 62.91 + 49.63 = 1:52.54

actual PR: Open 1:53.36, Relay 1:51.09(both in same year as 1500, 400 was 2 years older)

Seems about right, my open 800 has always been slower than I felt it should be, considering that I've run a full second+ faster 5 times on relays(official splits from Penn or indoors @ BU), and I don't know if the running start of a relay leg is worth that much in an 800.