# 4x4 Timer Interval Training — Norwegian 4x4 Interval Timer > Simple interval timer for the Norwegian 4x4 training protocol. (iPhone/iPad app by Kesem Solutions Pty Ltd.) - Source: https://appshunter.io/ios/app/4x4-timer-interval-training/id6759710803 (this page in markdown: same URL + `.md`) - Developer: [Kesem Solutions Pty Ltd](https://appshunter.io/developer/1751494198) - Category: Health & Fitness, Lifestyle - Price: Free - Rating: 2.00/5 from 1 App Store ratings · 1 written reviews indexed - Age rating: 4+ - Requires: iOS 13.0 · 12 MB - Languages: American English - Released: 2026-03-15 - Data updated: 2026-08-14 - Monetization: free - User reviews in markdown: https://appshunter.io/ios/app/4x4-timer-interval-training/id6759710803/reviews.md ## What is 4x4 Timer Interval Training? 4x4 Timer Norwegian Intervals is a simple, distraction-free interval timer designed for the Norwegian 4x4 training protocol, a well-known aerobic workout used to improve cardiovascular fitness and VO₂ max. The method is straightforward: 4 minutes ON. 4 minutes OFF. Repeat x4. This app guides you through the full session with clear visual timers and optional sound cues so you can focus on the workout, not the clock. Why Norwegian 4x4? The Norwegian 4x4 protocol has been widely studied in exercise physiology research as an effective way to train aerobic capacity and endurance. In recent discussions about longevity and brain health, Louisa Nicola highlighted this interval method as a powerful cardiovascular training approach used in performance and health optimization. This app simply helps you run the protocol consistently. Features • Simple 4x4 interval timer • Clear ON / OFF phase guidance • Optional sound cues for interval changes • Large easy-to-read timer for workouts • Session progress tracking and streaks • Minimal interface designed for training No accounts. No complicated setup. Just start when you're ready. How it works Tap Start Push hard for 4 minutes Take 4 minutes full rest Repeat for 4 rounds Total session time: about 32 minutes. Ideal for • VO₂ max interval training • Running intervals • Cycling workouts • Treadmill training • Stepper or rowing workouts • HIIT cardio sessions Research context The Norwegian 4x4 method has been studied in exercise science for its ability to stimulate high aerobic workload during short intervals. The app references this training approach discussed by neuroscientist and performance expert Louisa Nicola in conversations around cardiovascular fitness and long-term health. This app does not provide medical advice and is intended only as a simple training timer. ## Key features - Simple 4x4 interval timer - Clear ON/OFF phase guidance - Optional sound cues - Large, easy-to-read timer - Session progress tracking - Minimal interface ## Recent user reviews (1 of 1) All indexed reviews: https://appshunter.io/ios/app/4x4-timer-interval-training/id6759710803/reviews.md ### 2/5 — Don’t put your phone down *2026-04-25* The timer pauses if you put your phone in your pocket… so if I am running I have to hold my phone… also no interface for adjusting durations of work and recovery (maybe I want to match CERG 4x4 workout) ## Frequently asked questions about 4x4 Timer Interval Training ### What is the Norwegian 4x4 training protocol? The Norwegian 4x4 protocol involves 4 minutes of high-intensity exercise followed by 4 minutes of rest, repeated for a total of four rounds. This method is designed to significantly improve cardiovascular fitness and VO₂ max. ### How long does a session take with 4x4 Timer Interval Training? A complete session using the Norwegian 4x4 protocol, as facilitated by this timer, takes approximately 32 minutes. This includes the 4 minutes ON, 4 minutes OFF, repeated 4 times. ### Can I customize the intervals in 4x4 Timer Interval Training? This application is specifically designed for the Norwegian 4x4 protocol, meaning the intervals are fixed at 4 minutes ON and 4 minutes OFF. It does not offer customization for different interval lengths. ### Does 4x4 Timer Interval Training have sound cues? Yes, the app offers optional sound cues to alert you when an interval is changing. This allows you to focus on your workout without constantly checking the timer. ### What devices is 4x4 Timer Interval Training available on? This application is available for iPhone, iPad, and iPod devices. It is designed to run on Apple's iOS operating system. ### How often is 4x4 Timer Interval Training updated? The app was last updated on March 15, 2026, with version 1.0. Future updates will depend on developer plans for improvements or bug fixes. ### Does 4x4 Timer Interval Training have ads? No, this application is ad-free. It provides a distraction-free experience, allowing users to focus solely on their training session. ### What is the user rating for 4x4 Timer Interval Training? The app has a rating of 2.0 stars based on 1 rating. This indicates a limited amount of user feedback available at this time. ## Version history (last 1 release) ### 1.0 — 2026-03-15 No release notes. ## Apps similar to 4x4 Timer Interval Training | App | Rating | Price | Category | | --- | --- | --- | --- | | [Tabata & HIIT Timer - PEAKVO2](https://appshunter.io/ios/app/tabata-and-hiit-timer-peakvo2/id6532617265) | — | Free | Health & Fitness | | [Workout Timer: Interval & HIIT](https://appshunter.io/ios/app/workout-timer-interval-and-hiit/id6747319609) | — | Free | Health & Fitness | | [Unhook: Quit Lust & Reboot](https://appshunter.io/ios/app/unhook-quit-lust-and-reboot/id6744835988) | 4.5 (18) | Free | Health & Fitness | | [Recovery+](https://appshunter.io/ios/app/recovery-plus/id6752519740) | — | Free | Health & Fitness | | [Workout Timer - Interval Timer](https://appshunter.io/ios/app/workout-timer-interval-timer/id1580218001) | 4.6 (21) | Free | Health & Fitness | | [ChattyFit AI Personal Trainer](https://appshunter.io/ios/app/chattyfit-ai-personal-trainer/id6748089571) | 5.0 (4) | Free | Health & Fitness | ## More apps by Kesem Solutions Pty Ltd - [iUFlow- voiding bladder diary](https://appshunter.io/ios/app/iuflow-voiding-bladder-diary/id935581221) - [FODMAP AI Coach](https://appshunter.io/ios/app/fodmap-ai-coach/id6747165268) - [BoxAeye](https://appshunter.io/ios/app/boxaeye/id6748380773) - [10 Squats A Day](https://appshunter.io/ios/app/10-squats-a-day/id6759362572) - [Brain Card Color Game](https://appshunter.io/ios/app/brain-card-color-game/id6764464165) All apps by Kesem Solutions Pty Ltd: https://appshunter.io/developer/1751494198 ## Related topics [4x4 timer interval training](https://appshunter.io/ios/topics/4x4-timer-interval-training) --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-14.*