Question 26

Does a strong finish suggest unused capacity?

A next-race improvement of more than 2% occurred in 40.8% of pairs after a finishing section more than 5% faster than the preceding section, versus 33.9% after a similar or slower finish. This does not prove unused capacity in the earlier race.

The comparison conditions on returning for another recorded race, and the next race may have a different course and conditions.

583,670 linked race pairs · partial comparison

How we measured it. A finishing acceleration is the percentage change in pace from 21.75–24.85 to 24.85–26.22 mi. Group it as more than 5% faster, up to 5% faster, or similar/slower. Use consecutive cross-year linked pairs at most three years apart.

Full methodology & sources

Measure next-finish percentage change relative to the first finish, report its 10th/50th/90th percentiles within the first race’s pacing pattern, and the share improving by more than 2%. This does not measure effort reserves, account for absent follow-up, or establish what would have happened with a harder earlier effort.

For explicitly audited canonical-ID releases, validate unique matching CORE/FULL ID sets and matching recorded edition/name labels, then join by record ID with matching finish and all nine section durations. Legacy exports retain the one-to-one edition, trimmed lowercase name and full-timing join because their IDs are incompatible. Durations are compared to milliseconds. Keep only supplied non-ambiguous runner identities without conflicting recorded gender, inferred birth years spanning more than two years, or duplicate editions. These are candidate cross-race identities, not independently verified people; unlinked runners are absent. The linkage audit records which join was used.

Use complete, strictly increasing elapsed checkpoints at 3.11, 6.21, 9.32, 12.43, 15.53, 18.64, 21.75, 24.85 and 26.22 mi. Clock strings must parse as H:MM:SS or M:SS. No missing splits are interpolated.

Remove exact duplicate race records, ignoring database IDs, ingestion timestamps and source URLs. Retain finishes from 90 minutes to 12 hours with every section between 3.22 and 32.19 minutes/mi. These quality filters can exclude genuine unusual performances; the analysis describes this eligible cohort, not every entrant.

Full source records are available in public GitHub Releases. These chart tables require at least 100 eligible observations per cell for estimate reliability. Counts refer to finishes, linked pairs or event observations as specified in that answer.

These are observational results. Fitness changes, intentions, training, selection into the dataset and unmeasured conditions can explain differences. Outcome percentiles describe variation among performances, not confidence intervals or advice about the best strategy.

Apply the reviewed source-quality edition exclusions for this exact export after the timing checks. Known invalid split grids, incomplete ingestion, unreconciled HOLD editions and a selected top-finisher field do not contribute to the analyses or prior benchmarks. Report source exclusions separately; an already invalid timing row is not counted twice. Missing age or recorded gender alone does not exclude an otherwise eligible finish from the overall cohort. Other sparse editions are not declared incomplete merely from their size.

Marathons, years and recorded data. Chart samples may be smaller than the eligible analysis cohort.

Performance in the next race

Finish-time change (%) · below zero is faster

The line spans the 10th to 90th percentile. The dot marks the median.

More than 5% faster finish section
0%
Similar or slower finish section
0.6%
Up to 5% faster finish section
0.3%
View exact values and sample sizes
Group10th percentileMedian90th percentile10th percentile: ObservationsMedian: Observations90th percentile: Observations
More than 5% faster finish section-8.7%0%11.8%57,84957,84957,849
Similar or slower finish section-6.5%0.6%13.9%63,67263,67263,672
Up to 5% faster finish section-6.5%0.3%12.7%88,13888,13888,138

Next finish improved by more than 2%

Percent (%)

More than 5% faster finish section40.8%
Similar or slower finish section33.9%
Up to 5% faster finish section32.5%
View exact values and sample sizes
GroupNext finish improved by more than 2%Observations
More than 5% faster finish section40.8%227,060
Similar or slower finish section33.9%146,284
Up to 5% faster finish section32.5%210,326

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