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Features

Heart-Rate Zones

Zones from your real heart, colour-blind safe.

A heart-rate zone band during a workout

Runara computes your training zones from your actual heart-rate data read from Apple Health, your pick of the Tanaka or Karvonen formula, rather than a generic age guess.

By default the HR-zone band uses an intuitive cool-to-hot ramp; you can switch on an optional colour-blind-safe palette whose monotonic luminance ramp stays readable for deuteranopia, protanopia, and monochromacy alike. Either way, a single glance tells you which zone you’re in, even at full effort.

Two ways to anchor your zones

Pick the model that matches the data you trust. Both start from your real resting and peak heart rate in Apple Health, not a generic 220-minus-age guess.

Tanaka

% of maximum heart rate

HRmax = 208 - 0.7 × age

Estimates your maximum heart rate from age with the Tanaka equation, a closer population fit than the old 220 - age, then divides the zones as percentages of that maximum. Simple and dependable when you just want zones off your peak.

Karvonen

% of heart-rate reserve

target = rest + % × (max - rest)

Works from your heart-rate reserve, the span between resting and maximum heart rate, so every zone reflects effort relative to your own range. More individual, and more accurate the better your resting heart rate is known.

Which should you pick?

Tanaka keys the zones to your maximum alone; Karvonen folds in your resting heart rate, so for the same percentage it sets a higher, more personal target. Choose Karvonen when your resting heart rate is well measured, which Runara reads straight from Apple Health; choose Tanaka for a straightforward max-based split.

Readable for every kind of vision

By default the zone band uses the intuitive cool-to-hot colours most athletes already know. An optional colour-blind-safe palette is one toggle away; it is off unless you turn it on.

Default ramp

Z1
Z2
Z3
Z4
Z5

Cool blue, through teal, amber and orange, up to hot red. The meaning lives in the hue, the convention you can read at a glance. The trade-off: where red, orange and amber meet they can blur under red-green colour vision, and the brightness jumps around rather than rising with intensity.

Colour-blind-safe ramp

Optional
Z1
Z2
Z3
Z4
Z5

A viridis-derived ramp that climbs from dark purple to bright yellow. Its brightness increases steadily from Z1 to Z5, so the zones stay in the right order by luminance alone, even when hue can't be told apart. It is chosen specifically to stay distinct under deuteranopia, protanopia and monochromacy.

Both ramps map the same five zones (Z1 easy to Z5 max). The colour-blind option swaps the familiar hot/cold hues for a steady brightness ramp you can read no matter how you perceive colour.