Does Somvia need an Apple Watch?

It needs a wearable that writes overnight heart rate, HRV and sleep to Apple Health. Apple Watch does all three; some other watches write sleep but not HRV, and in that case the recovery score doesn’t appear, though load, thresholds, and race predictions still work from the workouts.

Where is the data processed?

Data is processed on the iPhone, and nothing leaves the phone unless the upload switch is turned on, and then only the chosen categories.

Which agents can read it?

Any agent that speaks MCP can read it, including Claude, ChatGPT, and self-hosted agents such as OpenClaw and Hermes.

Does it need a power meter?

It needs a power meter only for critical power; running thresholds and race predictions come from pace and heart rate alone.

Is there a free tier?

There’s a three-day free trial, then a subscription or a one-time purchase; there’s no permanent free tier.

Which models does it use?

It uses Bannister and Coggan for load, the 20- and 30-minute field methods for thresholds, Monod and Scherrer for critical power, Daniels and Gilbert for race times, and the 2022 FRIEND standards for cardio-fitness percentiles, all listed at somvia.app/training-science.

Somvia Archives -

News

Somvia review: threshold, critical power and race times from Apple Watch data

15 September 2026

the5krunner

Somvia estimates recovery, threshold pace, critical power and race times from Apple Health data already on…