Train Smarter With Every Heartbeat.
CardioEngine delivers real-time HR zone coaching using your Apple Watch or BLE chest strap — so every minute of cardio counts.
Generic HR Zones Miss the Point
Your heart rate zones are unique. A population formula can't tell you where your aerobic threshold actually sits.
220 Minus Age
A formula from the 1970s applied to every human regardless of fitness, genetics, or training history
No Zone Feedback
Most apps show which zone you hit after the workout. By then it is too late to adjust
Minutes Without Purpose
Logging cardio time with no weekly volume target or health-benefit tracking
Features
Zone Training, Not Zone Guessing
Every feature is built to keep you in the right zone at the right time, with data that proves your cardiovascular fitness is improving.
Real-Time HR Zone Tracking
See your current zone, target zone, and time-in-zone during every session. Adjust pace in the moment, not after the fact.
BLE + Apple Watch
Connects to Bluetooth chest straps for maximum accuracy, or uses Apple Watch optical HR. Your choice.
Adaptive Zone Coaching
Zones recalibrate as your fitness improves. What was Zone 4 last month might be Zone 3 now.
Weekly Minute Targets
Set a weekly volume goal in zone-minutes. CardioEngine tracks progress and recommends bonus sessions when you hit your target early.
Health Benefit Tracking
Resting HR and HRV trends over time. See the cardiovascular improvements your training produces.
Apple Watch Companion
Glanceable zone display on your wrist. Start, pause, and finish sessions without pulling out your phone.
How It Works
From Strap-On to Zone-Locked in 60 Seconds
Connect Your HR Source
Pair your Apple Watch or BLE chest strap. CardioEngine auto-detects the most accurate source available.
Set Your Zones
Choose a zone model or let CardioEngine calibrate from your data. Set a weekly minute target for your goals.
Get Real-Time Coaching
During sessions, see your live zone, time-in-zone, and pacing cues. After sessions, track health trends.
Compare
Not Another Workout Logger
CardioEngine is built for athletes who train by heart rate, not by feel. Here's how it stacks up.
Real-time zone coaching
BLE chest strap support
Adaptive zone recalibration
Weekly minute targets
Resting HR / HRV trends
Apple Watch companion
HealthKit-first (auto data)
Bonus session recommendations
| Feature | CardioEngine | Strava | Polar Beat | Apple Fitness+ |
|---|---|---|---|---|
| Real-time zone coaching | Partial | |||
| BLE chest strap support | ||||
| Adaptive zone recalibration | ||||
| Weekly minute targets | ||||
| Resting HR / HRV trends | Partial | |||
| Apple Watch companion | ||||
| HealthKit-first (auto data) | ||||
| Bonus session recommendations |
Screenshots
Data-Dense, Zero Noise
Everything you need to train by heart rate. Nothing you don't.
Dashboard
Weekly minutes, zone progress, and health benefit tracking at a glance.
Live Workout
Real-time zone coaching with BPM, elapsed time, zone distribution, and calorie burn.
Zone Profile
Personalized zones calibrated to your aerobic threshold, not your age.
History
Zone breakdown and effort tracked for every session.
Settings
Configure zone models, weekly targets, HR sources, and BLE monitors.
Stop Guessing Zones. Start Training.
Join the waitlist and be the first to get CardioEngine when it launches on iOS. Your cardio deserves better than 220 minus your age.
No spam. We'll email you once when the app launches.