Zone 2 AI: Vo2 Max & Endurance

Zone 2 AI: Vo2 Max & Endurance

Heart Rate Zones & Fitness Age

134 ratings
35 reviews
Free
In-App PurchasesWith Ads

Details

Released
March 16, 2025
Updated
October 29, 2026

Features

Zone 2 AI: Vo2 Max & Endurance video #1 for iPhone
Zone 2 AI: Vo2 Max & Endurance screenshot #2 for iPhone
Zone 2 AI: Vo2 Max & Endurance screenshot #3 for iPhone
Zone 2 AI: Vo2 Max & Endurance screenshot #4 for iPhone
Zone 2 AI: Vo2 Max & Endurance screenshot #5 for iPhone
Zone 2 AI: Vo2 Max & Endurance screenshot #6 for iPhone
Zone 2 AI: Vo2 Max & Endurance screenshot #7 for iPhone
Zone 2 AI: Vo2 Max & Endurance screenshot #8 for iPhone
Zone 2 AI: Vo2 Max & Endurance screenshot #9 for iPhone
Zone 2 AI: Vo2 Max & Endurance screenshot #10 for iPhone
iphone
watch
🖼️Get Icon
Icons↘︎

About

This app offers a comprehensive longevity protocol combining steady-state Zone 2 training with high-intensity sprints to improve mitochondrial efficiency and maximize VO2 Max. It personalizes training based on your data and projects future health outcomes.

✓Zone 2 training protocol
✓Norwegian 4x4 Sprint Protocol
✓Rate of Perceived Effort feedback
✓Zone2AI Power Score calculation
✓Predicted biological age and VO2 Max
✓Apple Watch haptic feedback
✓Syncs with Apple Health and other devices
Show original description

What's New in Zone 2 AI

2.7.5

October 29, 2026

Your Fitness Age, built on your VO2 max. Your Apple Watch or Garmin estimates your VO2 max. Zone2AI turns it into the age your heart and lungs perform at, then shows which habits move it: resting heart rate, Zone 2 consistency, strength and mobility. Your top heart rate comes from the highest effort you hold for 10 seconds, so your zones are built from your own training. Sprint days get credit first. Finish a hard session and the celebration comes right away; the app checks with you afterwards if anything looks unusual. The talk test speaks your language: easy to talk, can talk but it's uncomfortable, or can't hold sentences. Forgot to end a long workout? Zone2AI asks you, and counts the time your watch actually measured. Onboarding and Home are laid out for larger text sizes.

More
29

Subscriptions & In-App Purchases

Weekly Premium Access

Weekly subscription to all access premium features

$6.997 Days
7 Days trial
Price Updates
October 30, 2026→$6.99
August 13, 2026→$3.99
August 5, 2026→$6.99
May 4, 2026→$3.99
How to cancel Zone 2 AI subscription ⁉️

Events

Read more about 4-Week Zone 2 Challenge

4-Week Zone 2 Challenge

Hit your Zone 2 goal four weeks in a row.

Oct 19, 2026 — Nov 16, 2026

User reviews

Mohamed

Very good app has many updates and features not available in similar apps

Pathetic App

Utterly Pathetic app; what is AI in it? It is taking all Data from Garmin’s ready database and just fancy labelling same thing. Just a cheap gimmic to make money out of it

Response from developer

Nothing wrong with your Garmin. The sensors are excellent and we read them; that is the point. What we change is the number they get measured against. Garmin's zone chart is a generic training display, not calibrated for metabolic health. Its Zone 2 and the Zone 2 the longevity research is about are the same words for different things. That calibration is the AI. We take your full physiological picture, resting heart rate, measured max, VO2 max, and how hard each session actually felt to you, and compute your real, adaptive Zone 2 range. It moves as you get fitter. And the number has to be right to be worth anything. 150 minutes a week or more at a pace where you can still hold a conversation raises VO2 max, lowers resting heart rate, and improves markers like fasting insulin and hs-CRP. Aerobic fitness is among the strongest predictors of how long and how well people live. Train 10 bpm off the band and you do the work and get little of it. If yours looks wrong, I would like to see it. support@zone2ai.com reaches me. Rod, Founder of Zone2AI

Unacceptable Data Loss: Unstable Third-Party Software

I paid for this app expecting reliable Zone 2 tracking on my Garmin Venu 3S. Because Garmin’s operating system only allows one active tracking application at a time, choosing Zone 2 AI means you must completely bypass Garmin’s native, stable activity profiles. You are forced to entrust your entire session to this third-party software.
That trust is misplaced. After completing a strictly controlled 36-minute workout and tagging it as 'Other' upon saving, the app suffered a critical crash. It completely failed to write the .FIT file to the watch's hard drive, permanently deleting the session.
This is not a minor software glitch; it is the outright destruction of a valuable, well-performed workout. The permanent loss of these specific cardiovascular parameters actively corrupts the physiological data required to accurately evaluate progress and structure future training patterns.
Do not pay for software that jeopardizes your data integrity. You can achieve the exact same physiological targeting securely by setting custom High/Low Heart Rate alerts directly within Garmin’s native, crash-proof activity profiles.
Show more

Response from developer

Updating this, because part of what I wrote here is no longer true. The "Other" activity type that destroyed this session is gone, and that specific failure cannot recur. But I said saving was reliable, and it was not something I could stand behind. A later session on the same watch model was lost a different way. What changed since: the watch app no longer pushes any menu over a live recording, and that component was present in every reproduction we have. Stopping and discarding now happen on the workout screen itself, with two presses required to throw a session away. I am not calling this closed. It stays open on our side until the field data says the failure has stopped, and one scenario is still untested. That is the honest state of it. Rod, Founder of Zone2AI

Overall great stuff

Overall really good app. I went 15:49 in Colorado at elevation in the 5k recently off of CONSISTENT use of this app when I was in base training phase this summer. It helped me focus directly on my heart rate vs pace directly. There is a payment but I recommend getting the lifetime version because you’re going to START seeing results after about 3ish weeks. It takes time and consistency to start seeing training benefits. All in all this app has been a game changer in the way I look at easy runs. Hopefully I can go sub 15:30 in Colorado this year as a high school junior!!🤞🔥
Show more

Response from developer

The three-weeks line is the most useful thing anyone has written about this app, and it changed how I explain it to people. Zone 2 gives you almost nothing on day one, which is exactly why most people quit before it starts working. Congratulations on the 15:49. Rod, Founder of Zone2AI

Responsive developer and solid product

The application offers a lot that is not easily found elsewhere. What sets it apart is the developer is immediately responsive to questions or considerations for changes. It works very well and much of the way it works is highly customizable, which is likely from responses to customers. I use it multiple times per week and it has provided valuable insights to my training planning and execution.
Show more

Response from developer

Thank you. You've named the thing I care most about getting right: most of what's customisable in here exists because somebody wrote in and asked. If you ever hit something that doesn't work the way you'd expect, email me directly and it'll get looked at the same day. Rod, Founder of Zone2AI

Developer apps

FAQ

What is Zone 2 AI's primary focus?

Zone 2 AI focuses on building mitochondrial efficiency through Zone 2 training and maximizing VO2 Max with the Norwegian 4x4 Sprint Protocol, aiming for enhanced longevity.

How does Zone 2 AI personalize training?

The app creates a custom weekly prescription based on your age, gender, and resting heart rate, and uses RPE feedback to refine your Zone 2 heart rate range with each use.

Does Zone 2 AI track actual Zone 2 sessions?

Yes, it filters Apple Health data to identify actual Zone 2 sessions within your personal biosignal range, ensuring no false positives and adherence to your plan.

Can I use Zone 2 AI without an Apple Watch?

While Apple Watch haptics provide real-time feedback, the app syncs with various devices like Polar, Garmin, Strava, and WHOOP that write workouts to Apple Health.

What is the Zone2AI Power Score?

The Zone2AI Power Score measures your metabolic efficiency by calculating the power (Watts/kg) your body can generate while staying in a fat-burning state.

Does Zone 2 AI have ads?

Yes, Zone 2 AI contains advertisements. The app states it has no ads and no selling of data, but the monetization model indicates it is ad-supported.

What are the subscription options for Zone 2 AI Pro?

Zone 2 AI Pro offers several subscription plans, including weekly and annual options, with prices ranging from $3.99 per 7 days to $24.99 per year, and some plans include free trial periods.

How often is Zone 2 AI updated?

The latest version of Zone 2 AI is 2.7.5, and it was last updated on October 29, 2026. This indicates a relatively recent update frequency.