Method & evidence

Every number should say how much to trust it.

Your tests. Your thresholds. Your training profile.

Your tests set the starting point. Your training builds the picture.

Measured
Field-tested
Activity-derived
Estimated

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Evidence in view

Measured. Modelled. Clearly labelled.

Sources stay visible. Estimates stay labelled.

MeasuredModelledConfigured

Your physiology. In focus.

See what fuels your effort.

How carbohydrate and fat use change with intensity.

VO₂maxAerobic capacity

VLamaxGlycolytic rate

FatmaxPeak fat-oxidation intensity

LT1Aerobic threshold

LT2Upper threshold

VT1 · VT2Ventilatory thresholds

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● Carbohydrate● Fat

EasierEffort →Harder

Schematic illustration · not a personal estimate

ⓘ

Brooks & Mercier (1994); Maunder et al. (2018).

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