Environmental Resilience | Heat & Altitude

Descripción

Fitness tested in a cool room doesn’t tell you what happens when the heat is real — and for anyone racing somewhere hot or humid, that gap matters. This test exposes you to a controlled hot, humid environment on the bike and measures how much your physiology drifts as thermal strain builds, at the exact same power output throughout.

The structure is a fresh-baseline / heat-exposure / heat-stressed re-test sandwich: a 10-minute steady hold at target power fresh, mask on; a 30–60 minute block in the hot room to build real thermal load, mask off so you can breathe and fuel freely; then an identical 10-minute hold at the exact same watts, mask back on. Because the work rate never changes, every difference between the two holds is what the heat cost you, not a change in effort.

Four markers are compared, each banded independently, with heart rate as the primary heat signal:

– Cardiovascular strain (HR) — the clearest heat marker; a rising HR at the same power shows your body diverting blood to the skin to shed heat
– Ventilatory drift (VE) — the respiratory cost of the thermal response
– Economy creep (VO2) — oxygen cost for the same power, i.e. movement economy decaying under heat
– Substrate drift (RER) — how far your fuel mix shifts toward carbohydrate under thermal load

Your report also translates the room’s temperature and humidity into a WBGT heat-stress score and an equivalent dry-air temperature, so you know exactly how hard the conditions were — not just what the thermometer said.

Biomechanics, lightly: alongside the physiology, IMU sensors log a light on-bike movement and postural stability check through the heat-exposure block — a supporting read on whether fatigue and heat are affecting your position and form, not the main focus of this test.

What you’ll get:

– Cardiovascular strain (% HR rise) and thermal-strain classification — your primary heat result
– Ventilation, economy and substrate drift, banded
– WBGT heat-stress score and equivalent dry-air temperature for the room you were tested in – A light IMU-based form/stability flag alon
– A heat-acclimation training plan targeted at whichever marker drifted most

Before you test: arrive fasted for 4+ hours, no caffeine or stimulants for 6 hours, no heavy legs or high-intensity work in the 48 hours prior, and arrive well line invalidates the heat comparison, sothese matter.

Coming soon: an altitude-resilience companion test in our hypoxic chamber, for athletes who need to know how they cope with thin air as well as heat.