Helix

Guides

Do the thing, properly.

Field tests you can run this week, Apple Watch numbers explained without hand-waving, and training that actually moves the metric. Written by people who do this stuff, with the calculators built in.

01

Test protocols

Field tests you can run this week: measure the number properly, then score it on the spot.

02

Apple Watch

Getting real signal out of the watch you already own: HRV, sleep, heart rate and what the numbers mean.

03

Improve a metric

The training and habits that actually move VO₂max, HRV and sleep debt, with the timelines to expect.

04

Training

Programming built on how muscles actually recover.

05

Health

Reading your own health data without a decoder ring.

Free tools

35 calculators, no signup.

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Docs

Everything the app does.

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