Trail Notes | Training Plans & First Ultra

how to know it's actually working

Fitness Benchmarks

For Her Training.

The promise of training is simple: put in the work and you get fitter. Knowing whether it is actually happening is the part nobody hands you a clear answer for, and the standard answers were rarely built for a female body.

Endurance adaptations arrive slowly and quietly. They almost never show up in a single workout, which is why the runners who reach their long-term goals are the ones who track a handful of reliable benchmarks over months, not days. You do not need a lab to do this well. You need consistency and the right markers.

For women there is an extra layer worth naming. Some of the most common benchmarks, especially heart-rate based ones, shift with your menstrual cycle, your fuelling and your iron status. That does not make them useless. It means you have to read them with those factors in mind, and it means a few female-specific markers belong alongside the classic ones, because for us, health and fitness are not separate questions.

Below are three tiers of benchmarks, organised by how much structure and technology you have, followed by the female-specific markers every woman building toward a first ultra should be watching.

Tier 1: the accessible benchmarks

These need almost no technology, just a heart-rate monitor and a running app, and they work even if you are not following a structured plan. The first is your endurance heart-rate trend. As your heart grows stronger and pumps more blood per beat, it needs fewer beats to do the same job, so over three to six months your average heart rate on easy runs can gradually drift down. The effect is clearest for newer runners and those returning after time off.

The female caveat matters here. Your heart rate also moves with cycle phase, hormonal contraception, heat and sleep, so a single high-HR run is not a sign you have lost fitness. Compare like with like, the same route, effort and weather, and read the trend across a full cycle or two rather than day to day. The second Tier 1 tool is repeated segment times on the same stretch of trail or road, watched as a trend in comparable conditions, not chased as a personal best on every run.

Tier 2: benchmarks for structured plans

If you follow a structured plan with dedicated interval sessions, you can compare the same workout across training blocks. The idea is simple: repeat an identical session, say four times ten minutes at threshold effort, at comparable points in different blocks, and look at the output. If your grade-adjusted pace improves at the same effort, your threshold has likely risen. For trail runners, a grade-adjusted pace metric is far more honest than raw pace, because it accounts for the climbing.

Keep the comparison clean: same workout structure, similar weather, and crucially a similar level of fatigue. Comparing a session run fresh against one buried deep in a heavy block is a fatigue comparison, not a fitness one. For women, there is one more variable to hold steady where you can. Because perceived effort and physiological response to a standardised session can shift across the menstrual cycle, try to repeat benchmark workouts at a similar cycle phase, or at minimum record the phase so you can interpret an off day correctly.

Tier 3: precision testing

With access to a lab, a lactate threshold test gives the clearest picture, tracking the pace at which lactate begins to climb steeply. Reaching that threshold at a faster pace than before is a precise sign of progress, and the same test can reveal how much fat and carbohydrate you burn as you run, which matters for a female body that tends to lean on fat well during long efforts. Most runners who test do so once or twice a year at comparable points in the season.

No lab is fine. A field test approximates it well: a maximal thirty-minute effort on a flat course, where you take your average heart rate and your average pace over the final twenty minutes as your threshold heart rate and threshold pace, discarding the first ten minutes while your effort and heart rate settle into a true sustained ceiling. Leave at least eight weeks between field tests, arrive rested, and, as with every benchmark, try to schedule them at a similar cycle phase so you are comparing fitness to fitness.

The benchmarks built for her

Pace and heart rate tell only part of a woman's story. For a female runner, some of the most important benchmarks are health markers, because fitness built on an under-fuelled, under-recovered body is borrowed, not earned. These belong in your tracking right alongside your splits.

If you take only one idea from this section, let it be this: for a woman, a regular cycle and healthy iron are performance benchmarks, not side issues. When they slip, your splits will follow, often months before you understand why. Tracking them is how you protect the fitness everything else is trying to build.

How to combine them

Layer the tiers rather than choosing one. Start with Tier 1, watching for a gentle downward drift in easy-run heart rate and a faster trend on chosen segments across weeks and months. If you train to a structured plan, add Tier 2 by comparing the same interval session block to block. Once or twice a year, invest in Tier 3 with a field or lab test at a consistent point in your season.

Then run the female markers continuously underneath all of it. Cycle regularity, fuelling, iron and durability are not annual tests; they are the ongoing health context that tells you whether your rising fitness is sustainable or borrowed. Track consistently, give every trend months to declare itself, and compare yourself only ever to your own past. Adaptation is entirely individual, and for a first ultra, patient and healthy beats fast and fragile every time.

measure what matters, compare only to you

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