CIM's Fastest Field in Six Years Makes the Case for December in Sacramento

California International Marathon has spent the past two years rewriting what its field can do. In 2025, 8,168 runners crossed the finish line with a median time of 3:43:13 — the fastest median in any edition on record here — and 2,469 of them earned Boston qualifying marks, a rate of 30.2%. This is a point-to-point, net-downhill road course that regularly delivers what it promises.

By the numbers

Field size has climbed steadily from 7,470 finishers in 2019 to a peak of 9,182 in 2023, before settling at 8,168 in 2025. More significant than the headcount is what's happened to the median: from 3:56:55 in 2019 to 3:43:13 in 2025, a six-year improvement of more than thirteen minutes. The men's median followed the same arc — 3:46:42 in 2019 down to 3:33:45 in 2025 — as did the women's, from 4:11:24 to 3:56:41. The BQ rate has climbed from 25.2% in 2019 to 30.2% in 2025, the highest across all six editions in the data.

How the course runs

CIM runs point-to-point from Folsom to Sacramento on a net-downhill course that loses 333 feet over 26.2 miles. The elevation profile is genuinely downhill in character, with the most concentrated descent coming early — a 101-foot drop between miles 2.2 and 3.8 — and the longest sustained descent of 116 feet threading through miles 15.1 to 21.8 at a gentle average grade of 0.3%. The final miles are essentially flat.

The 2025 fade curve shows a field that opens conservatively and holds shape through halfway before the back half extracts its toll:

The field runs its fastest segment between miles 3.1 and 6.2 (8:12/mi), holds steady through the half at 8:17/mi, then begins drifting from the 30K mark onward. By the 40K checkpoint the median pace has slipped to 8:52/mi — a 40-second-per-mile drift from the early miles. The slight uptick to 8:35/mi in the closing 1.3 miles reflects the finish-line surge that appears in most large marathon fields.

Pacing patterns

Back-half slowdown is the norm at every major marathon, and CIM is no exception — but the degree varies sharply with conditions. In 2023, with temperatures reaching 63°F and 68% humidity, 85% of the field ran positive splits and the average second-half slowdown hit 11.8%. In 2025, with race-day temperatures peaking at just 46°F, that figure dropped to 6.3%, and the share running negative splits rose to 1,479 runners — the highest count across all six editions. The coldest, calmer editions consistently produce the tightest pacing.

The weather question

CIM's December slot in Northern California has delivered a range of conditions: light rain and wind in 2019 and 2022, mild and partly cloudy in 2021 and 2024, and the cold, still, overcast morning in 2025 that produced the field's fastest median. The 2026 forecast — 38–48°F, mist, wind around 8 mph, 93% humidity — sits closer to the 2022 profile (46–56°F, light rain, 7 mph) than to the ideal 2025 morning. That 2022 edition saw an average slowdown of 10.8% and 81% positive splits, suggesting the mist and wind will matter more than the temperature alone.

What it takes

In 2025, breaking 2:50:34 placed a runner in the top 10% of the field. The top 25% threshold was 3:11:22, and the 75th percentile sat at 4:25:27. The men's winning time was 2:09:29; the women's was 2:24:09 — both among the fastest in the race's recent history, though the 2024 course records of 2:07:35 (men) and 2:24:28 (women) remain the benchmarks.

What to watch

The BQ rate is the most closely watched number at CIM, and it has now exceeded 27% in every edition since 2021. Whether the 2026 field can match or surpass 2025's 30.2% — the six-year high — will depend heavily on how the mist and wind play out across the back half. A second storyline is field composition: women's finishers peaked at 3,646 in 2023 and have declined in the two editions since; whether that trend reverses will shape the overall median. Finally, the 2025 median of 3:43:13 broke a plateau that had held near 3:49 across 2021–2023 — whether that improvement consolidates or proves weather-dependent is the central question the 2026 data will answer.