Places the power of a cycling test at 3 mmol/L ("OBLA 3.0") and at 1 mmol/L above the resting lactate
("Bsln + 1.0") among people of the same sex and age, on the reference percentiles of the German population aged 14
to 64 (Fiedler et al., 2025): in watts and, with body_mass, in watts per kg.
Arguments
- x
The result of
lactate_threshold()for a cycling test.- age
Age in years, from 14 to 64.
- sex
"female"or"male"(or"F","M").- body_mass
Body mass (kg), for the percentiles of power per kg, or
NULL.
Value
a lactate_reference tibble with one row per threshold and unit: method, value, unit, the
percentile, and the standing in plain words, from the published percentiles it falls between: "top 5%",
"top 10%", "top 25%", "upper half", "lower half", "bottom 25%", "bottom 10%", "bottom 5%", or beyond the
2.5th and 97.5th, "top 2.5%" and "bottom 2.5%".
Details
The percentiles come from 2,389 women and 2,801 men of two national health surveys (KiGGS wave 2 and DEGS1), tested
on a cycle ergometer from 25 W with 25 W more every 2 min, at 60-80 rpm, with earlobe blood analyzed on a Biosen
C-Line, until 85% of the age-predicted maximal heart rate. Their thresholds were computed with lactater "on a 3rd
degree polynomial with the baseline (step 0) data" included, so the two thresholds are computed here in the same way,
whatever fit and include_baseline the test was analyzed with: they can differ by a few watts from its table. Read
the result with three limits in mind:
The protocol. Percentiles transfer only between tests run the same way. Shorter stages put the thresholds at higher intensities (Bentley et al., 2007), so a test with 3-min stages looks a little weaker against these 2-min norms. A warning is given when the steps of the test are not 25 W, it has no resting sample, or the
stage_durationorsitegiven tolactate_threshold()are not 2 min and earlobe; without them, the stage length and the sampling site are yours to check.The population. These are values of the general population, not of athletes: most trained cyclists land above the 97.5th percentile.
The precision. The percentile is interpolated between the nine published percentiles, from the 2.5th to the 97.5th, on the normal scale and at the exact age. Beyond the 2.5th or the 97.5th it is
NA, andstandingsays "top 2.5%" or "bottom 2.5%".
References
Fiedler J, Thron M, Altmann S, Haertel S, Barsch F, Schlenker L, Krug S, Boes K, Woll A. Reference standards for power at the lactate threshold 2 for cycle ergometry throughout the lifespan in Germany. Journal of Sports Sciences. 2025;43(16):1654-1664. doi:10.1080/02640414.2025.2517913
Bentley DJ, Newell J, Bishop D. Incremental exercise test design and analysis: implications for performance diagnostics in endurance athletes. Sports Medicine. 2007;37(7):575-586.
Examples
results <- lactate_threshold(demo_data, intensity, lactate, heart_rate, plot = FALSE)
reference_percentiles(results, age = 31, sex = "male", body_mass = 72)
#> # Reference percentiles: men aged 31 in Germany (Fiedler et al., 2025)
#> # Reference test: cycle ergometer, +25 W every 2 min, earlobe blood;
#> # general population, not athletes
#> method value unit percentile standing
#> <chr> <dbl> <chr> <dbl> <chr>
#> 1 OBLA 3.0 130 W 53 upper half
#> 2 Bsln + 1.0 105 W 41 lower half
#> 3 OBLA 3.0 1.8 W/kg 76 top 25%
#> 4 Bsln + 1.0 1.45 W/kg 63 upper half