Brown Family Sports Inc. · Kelowna, British Columbia

Research

The models behind our calculators, published in full — the physiology they rest on, every coefficient they use, and the places where they are weakest.

Why we publish the equations A pace prescription that cannot be checked is not a prescription, it is an assertion. Each report here states its coefficients, names its sources, and marks the parameters that are operating choices rather than measured values — so that its errors are findable by people who did not write it.

1 report

BFS-TR-2026-01

Environmental and Body-Mass Determinants of Distance-Running Pace

A quantitative model for race-day pace adjustment, with its derivation and limits

Why a goal pace calibrated in cool training weather becomes a different physiological task on a warm, humid morning — and how much slower to run instead. Reviews the evaporative basis of heat loss, the humidity weighting inside WBGT, the quadratic temperature–performance curve from 1.79 million marathon finishers, the heat-storage penalty carried by larger runners, and the mechanisms that turn banked early time into a late collapse. Then specifies the Total Heat Load model in full, including the two points where its calibration knowingly departs from the evidence.

Thermoregulation Pacing Model specification 1 September 2026 14 references ~18 min read
Read the report →

Companion reading. Each technical report has a plain-language counterpart in Articles — for this one, Heat, Humidity & Weight: The Case for Actually Running Slower. The models themselves run in the pace calculators.