Norwegian 4x4 Protocol vs Viscera
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Norwegian 4x4 Protocol
This app guides you through the effective Norwegian 4x4 interval training method to boost cardiovascular performance and endurance. It features a precision timer, heart rate zone tracking, and progress monitoring for scientifically proven results.
- Precision 4min work / 3min rest cycles
- Heart rate zone tracking (90-95% max HR)
- VO2 Max improvement tracking
- Multiple HIIT workout protocols
- Progress monitoring
- Universal cardio training support
- Offline functionality
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Norwegian 4x4 HIIT Timer — Interval Training & VO2 Max BOOST VO2 MAX WITH NORWEGIAN 4X4 PROTOCOL WORKOUTS Train smarter with the Norwegian 4x4 protocol, one of the most studied HIIT methods for improving cardiovascular performance and endurance. A precise, distraction-free timer guides every interval so you can focus on the effort. KEY FEATURES: - Norwegian 4x4 Timer - Precision 4min work / 3min rest cycles - Heart Rate Training - Track 90-95% max HR zones - VO2 Max Improvement - Scientifically proven results - HIIT Interval Timer - Multiple workout protocols - Progress Tracking - Monitor your fitness transformation - Universal Training - Running, cycling, rowing, any cardio, you name it - Offline Ready - No internet required during workouts - Haptics Feedback and Vibrations - Countdown before the start - Customizable Warmup session length - Customizable Cooldown session length WHAT IS NORWEGIAN 4 BY 4 TRAINING? The Norwegian 4x4 protocol is a revolutionary HIIT method featuring: - 4 intervals of 4 minutes at 90-95% max heart rate - 3 minutes active recovery between intervals - Proven results: Increase VO2 max by up to 10% in 8 weeks - Elite approved: Used by professional athletes worldwide WHY CHOOSE NORWEGIAN 4X4 INTERVAL TRAINING? - PROVEN RESULTS: Sports science research shows significant cardiovascular improvements - BEGINNER FRIENDLY: Complete guide for Norwegian 4x4 workout beginners - CUSTOMIZABLE: Adapt the Norwegian 4 x 4 protocol to your fitness level - COMPREHENSIVE: Includes warm-up, cool-down, and recovery protocols - VALIDATED: Mention in Tim Ferriss' Blog PERFECT FOR: - Athletes seeking performance gains with Norwegian 4x4 workouts - Fitness enthusiasts wanting efficient HIIT interval training - Anyone improving cardiovascular health through proven protocols - Runners, cyclists, rowers using Norwegian 4x4 interval training HOW OFTEN NORWEGIAN 4X4? - Our app includes guidance on optimal training frequency and recovery for maximum VO2 max gains. START YOUR NORWEGIAN 4X4 TRANSFORMATION Join thousands who have revolutionised their fitness with the Norwegian 4x4 protocol training. Download the ultimate Norwegian 4x4 workout app now! Download today and start training with the Norwegian 4x4.
Viscera
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Viscera – Estimate Your Visceral Fat Area (VFA) Viscera is a simple health tool that helps estimate visceral fat area (VFA) using validated formulas for men and women. Visceral fat is the fat stored around internal organs, which may be associated with metabolic health and overall well-being. How it works Input a few basic body measurements. The app calculates your estimated visceral fat area (VFA). Separate formulas are applied for men and women, based on scientific research. Source The calculation formulas are derived from research by the Luxembourg Institute of Health: Amaro J, Santos O, Marques O, et al. Anthropometric surrogate models for visceral fat: a new insight. European Journal of Clinical Nutrition (2021). Read the study Disclaimer Viscera is intended for informational purposes only. It does not provide a medical diagnosis or treatment advice. Results are estimates and should not replace consultation with a qualified healthcare professional. If you have concerns about your health, body composition, or risk factors, always seek advice from your doctor or healthcare provider.
Screenshots
Verdict
The clearest difference is price: Viscera at $1.99 against Norwegian 4x4 Protocol's $5.99. Norwegian 4x4 Protocol's advantage is chart position (#138 vs unranked). On update cadence, ads, in-app purchases and device support there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Norwegian 4x4 Protocol costs $5.99 and Viscera $1.99 up front. Neither carries in-app purchases, so what you see is what you pay.
Norwegian 4x4 Protocol ships an update every 3 weeks, Viscera monthly. The most recent releases landed on October 18, 2026 and October 17, 2026 respectively.
| Parameter | Norwegian 4x4 Protocol | Viscera |
|---|---|---|
| Price | $5.99 | $1.99 — better |
| Rating | 4.3 (54 ratings) — better | — |
| Positive reviews | 25.0% of reviews | — |
| Number of ratings | 54 — better | — |
| Update frequency | Every 3 weeks — better | Monthly |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Paid | — |
| Best chart rank | #138 — better | — |
| Devices | iPhone, iPad | iPhone, iPad |
| Requires iOS | 17.6 — better | 18.5 |
| Further details — not scored | ||
| Size | 5 MB | 3 MB |
| Age rating | 4+ | 17+ |
| Developer | Nikita Yampolski | Hans Christian Christensen |
In-app purchases
Norwegian 4x4 Protocol
No in-app purchases
Viscera
No in-app purchases
Questions
Is Norwegian 4x4 Protocol free?
Is Viscera free?
Do Norwegian 4x4 Protocol or Viscera have ads?
Which is updated more often, Norwegian 4x4 Protocol or Viscera?
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