Age-grading, explained

The problem it solves

Raw time rewards being 28. But a 62-year-old climbing Ascutney four minutes slower than the fastest rider may be putting in the better performance for their physiology, and a series that runs on raw time alone makes that invisible.

Age-grading adjusts every finish so performances can be compared across ages on a level footing.

How it works

Each finish is adjusted from a baseline age of 40. Below 40, times stand as ridden. Past 40, the expected cost of each year is credited back, and an age-graded time answers one question: what would this ride be worth from a 40-year-old?

The curve, exactly

Age-grading in BUMPS is built on the research of Ray Fair, the Yale economist and lifelong masters athlete who has spent decades measuring how endurance performance declines with age. By studying age records across running, swimming, and cycling, Fair showed that the slowdown is remarkably consistent: gradual and nearly linear through the fifties and sixties, then steepening in the later decades. His published aging factors are the standard reference for masters age-grading, and the BUMPS curve is our adaptation of that work to hillclimb racing.

Here is how the site computes it. Every age from 40 up gets a factor, a multiplier that says how much slower a typical rider of that age is than their 40-year-old self. The factor table is built one year at a time:

1. Age 40 is the baseline. The factor is exactly 1.0, and riders under 40 are not adjusted at all: their times stand as ridden.
2. From 40 to a breakpoint age, each year compounds a flat decline rate: 1.19% per year for men (through age 74) and 1.41% per year for women (through age 69). Compounding means age 41 is 1.0119 times the age-40 factor, 42 is 1.0119 times that, and so on, the same way interest compounds.
3. Past the breakpoint, aging accelerates. The annual rate itself grows by 0.1 percentage points every additional year, so a man's decline is 1.29% at 75, 1.39% at 76, and the compounding continues on those growing rates. This is the steepening Fair's data shows in the later decades.
4. Above age 90, the factor holds at the age-90 value.
5. Nonbinary riders are graded on the average of the men's and women's curves.

Your age-graded time is your actual time divided by your factor. Some points along the table the site actually uses:

Read one row aloud and the idea clicks: a 70-year-old woman is expected to be about 52% slower than she was at 40, so her time is divided by 1.524 before it meets anyone else's. A 62-year-old man carries a factor of roughly 1.30, which turns a 1:10:00 up Washington into an age-graded 54 minutes, the ride a 40-year-old would need to match the performance.

The table is frozen for the season, so every rider is graded against the same curve all year, and the graded time is scored on the same 100-point scale as raw results.

Where you'll see it

Flip Age-Graded Mode at the top of any page. Standings, badges, PR tags and podiums all recalculate on that basis, it's a parallel universe of the whole series, not a separate column. Some of the most impressive rides in BUMPS history only become visible this way.

The fine print

Grading uses your age in the race season, and the adjustment is applied to time, then scored on the same 100-point scale as raw results. Neither mode replaces the other, the series keeps both leaderboards, and bragging rights in each.