◉ Lactate-anchored metabolic profile

Lactate test → full metabolic profile

One unified wizard: athlete inputs, a 15-second sprint VLamax, and the 5–9 stage step test. We fit VO₂max from the curve and return MLSS, LT1, Fatmax, substrate oxidation, training zones — and an honest sensitivity readout.

1. Athlete

Body mass scales the absolute substrate values (g/min). Sex influences reference-range comparisons only.

Sex

♂ Male ♀ Female

Sport

Running Cycling

Body mass (kg)

2. Sprint VLamax

A 15-second all-out sprint with pre- and post-sprint blood lactate gives us your maximum glycolytic rate (VLamax) — the input that anchors the rest of your metabolic profile.

3. Step test stages

Add 5–9 stages. Each stage is 5 minutes at a fixed effort, with a 1-minute standing rest to sample lactate. Final stage should land in the 7–10 mmol/L range to anchor the upper curve.

Testing altitude — optional

Above ~800 m / 2,600 ft, paces are converted to sea-level equivalents before fitting, so VO₂max and zones match a sea-level test (Faulkner 1968 / Daniels 1979); the zone table also shows altitude-equivalent paces. Boulder ≈ 1650 m, Denver ≈ 1600 m.

Stage	Pace	Duration (min)	Lactate (mmol/L)	HR (bpm) — optional