Zone 2 Guardrail

Stay in Zone 2 without watching your wrist.

Zone 2 — your easy aerobic base zone — only builds endurance if you actually stay in it. Push too hard and you lose the benefit. But glancing at your heart rate every few seconds breaks your rhythm and ruins the workout.

Zone 2 Guardrail keeps the line for you. Set your ceiling once, start a session, and put your wrist down. The moment your heart rate drifts above your cap, you feel a firm buzz — a clear “ease off” you can feel without looking. Settle back into zone and a gentle tap confirms you’re good.

Train by feel. Let the watch watch the numbers.

What it does

• Haptic-first alerts. A strong wrist buzz the instant you go above your Zone 2 ceiling. It fires whether or not sound is on, so you stay guarded in silence.
• Set your ceiling your way. From your age automatically, from your measured max heart rate, or a fixed number you choose.
• Live session feedback. See your time in zone, time above the cap, and percentage over — at a glance and in your end-of-session summary.
• Saves to Health. Each guarded session is logged as a workout alongside the rest of your training.
• Focused and private. No feeds, no accounts, no analytics. Your data stays on your device.

Built for the Apple Watch

A single-purpose tool that does one thing well. Runs right on your wrist — no phone needed during a workout.

Requirements: Apple Watch running watchOS 10 or later (Series 4 and newer, all SE models, Apple Watch Ultra).

Pricing

Try it free for your first 5 guarded sessions. If it earns a place in your training, unlock unlimited sessions forever with a single one-time purchase. No subscription.