Zephyr Lab

Running, analyzed.

Your watch records more than a finish time. ZephyrRun turns its running data into pace, heart rate, intervals, recovery and trends you can actually understand — with insights generated on your device.

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Activities

Start from the run

Keep the activities that matter to you within reach, with the numbers you care about ready at a glance.

Run detail

More than distance and pace

Pace, heart rate, zones, intervals and recovery, shown on one timeline.

Phases

Phase-aware running analysis

A run isn't one effort from the first to the last minute. ZephyrRun identifies warmups, cooldowns, hills, sprints, work intervals and recoveries, then compares the numbers that belong together.

You

Your physiology

Max HR, recovery HR, pace-HR progression, and your zones from that. The more you run, the better it fits.

Pro Trends

The long game

Follow pace, volume, load and performance across weeks and months. Compare periods side by side and see where the work is actually moving you.

Pro Form

How you run, not just how fast

Pro Insights

AI insights, on device

ZephyrRun already understands the structure of your workout. On-device intelligence looks across that analysis to surface the changes and patterns worth your attention.

ZephyrRun activities
A tempo run on one timeline — phases, pace, heart rate and zones
An interval run split into its phases
Physiology — max, resting and recovery heart rate, pace at heart rate, and zones
Trends — Pro, dark
Running form — stride, cadence, ground contact and power
An insight, read off the run
Zephyr Intelligence

Built to understand the workout before explaining it.

ZephyrRun doesn't ask AI to make sense of raw sensor data. Running metrics are processed and analyzed first, then relevant context is passed to on-device intelligence for interpretation. The result is grounded in your actual workout, without uploading your fitness history to an AI service.