How are ULTRA Points calculated for a race result?
ULTRA Points (UP) are awarded to a race result based on that race's required effort factor and the individual result's Performance Index (PI).
The exact formula for the ULTRA Points calculation is:
Race result UP = Race effort factor * Race result PI / 100
In plain language, what we're trying to capture in the ULTRA Points calculation is a combination of how hard the race you finished in was, as well as how hard you went in that race compared to other participants.
The race result PI provides a measure of how strong the performance of a given runner was in a race compared to other runners in that race. A detailed account of how the race result PI is calculated can be found here.
The race effort factor aims to capture the difficulty of the race - which is not a very straightforward thing to do. Obviously, longer races are harder than shorter races, but then all kinds of other factors can affect the difficulty of a race, such as elevation gain, terrain, weather, etc. All of which come together in very different ways for different races.
So, to keep things simple (and still, hopefully, fairly accurate), we decided to base the calculation of the race effort factor on the median race result. (We explain in more detail what the median race result is here, but, in short, the median race result is the result at the middle of the list of race results.)
Why the median race result?
Because the median race result captures everything about the difficulty of a race. Longer races will have a longer median result. So will races with more elevation gain. For the same race run in two consecutive years with different weather conditions, the median results from those two races will also reflect that difference in weather conditions.
Notice that, because the median result represents the "average" performance (sort of, but let's not get overly technical) in the field, it will not be affected by exceptionally strong performances at the front of the field (aka Jim Walmsley decided to show up for the race). The median race result is unchanged whether the race was won in 10h or 9h 45mins, unless that difference is due to overall race difficulty factors, in which case that difference will also be reflected across the entire race field.
To understand exactly how the ULTRA Points calculation works, let's look at some concrete examples:
Example 1: The median race result for a 50mi race was 10:00:00 (10h), and your finish time was 9:30:00 (9.5h).
The Performance Index for your race result is 105.3 (you can find more details on the PI part of this calculation here).
The effort factor for this race is the median finish time in seconds divided by 1,000. The median finish time for the race was 10h (=36,000 secs), so the effort factor for this race is 36.
And so the ULTRA Points for this race result are calculated as 36 * 105.3 / 100 = 37.9.
Example 2: The median race result for a 50mi race was 10:00:00 (10h), and your finish time was 11:00:00 (11h).
The Performance Index for your race result is 90.91 (you can find more details on the PI part of this calculation here).
The effort factor for this race is - like in Example 1 - 36. So the ULTRA Points for this race result are calculated as 36 * 90.91 / 100 = 32.7.
Example 3: The median race result for a 24h race was 150km, and your finish distance was 180km.
The Performance Index for your race result is 120 (you can find more details on the PI part of this calculation here).
The effort factor for a 24h race is 24 * 3,600 secs / 1,000 = 86,400 secs / 1,000 = 86.4.
So the ULTRA Points for this race result are calculated as 86.4 * 120 / 100 = 103.7.
Example 4: The median race result for a 24h race was 150km, and your finish distance was 120km.
The Performance Index for your race result is 80 (you can find more details on the PI part of this calculation here).
And the ULTRA Points for this race are calculated as 86.4 * 80 / 100 = 69.1.
Not all race results can accrue ULTRA Points, however. As discussed in the PI calculation methodology, backyard ultras, races with fewer than 20 participants and non-standard fixed-time races (fixed-time races other than 6h, 12h, 24h, and 48h) are excluded from both PI and UP calculations.