Live zone guidance
See whether you’re below, in, or above your target range.
Norwegian 4x4,
guided from your wrist.
Ramp4x4 coaches every hard interval and recovery with live heart-rate guidance, voice, and haptics on Apple Watch.
Made for iPhone and Apple Watch by Archline Labs.
One workout.
Every cue handled.
Ramp4x4 keeps the structure, heart rate, and transitions in one place so you can stay with the effort.
Four guided intervals
Warmup, 4 × 4 minutes, active recoveries, and cooldown.
Voice + haptics
Choose voice cues, phase haptics, interval-ending cues, and high or low heart-rate alerts.
Time in target
Review measured time inside your saved target range, with interval-by-interval detail.
Progress that means something
Follow your Apple Health cardio fitness estimates, workout history, and 8-week plan.
Train where you train
Choose your activity, use Apple Watch or a compatible Bluetooth heart-rate monitor, or train with Timer Only.
Start on your wrist.
Finish with the evidence.
Start on Apple Watch
Open Ramp4x4 and begin the complete session from your wrist.
Warm up into the session
Follow the countdown while your heart rate rises gradually.
Complete four guided intervals
Push, hold, and recover with live zone guidance at every phase.
Review heart-rate performance
See workout quality, measured time in target, and interval results.
See the workout. Then see the work.
Actual app screens with sample workout data, from your next session to the final interval review.
1 / 5
Built for one workout — and honest about it.
Ramp4x4 is a focused Norwegian 4x4 coach, not a generic fitness platform. The complete guided workout is free; Ramp4x4+ adds deeper history, analysis, and planning.
- Apple Health sync
- Your health data stays on your devices
Learn the method.
Use the app.
RampWorkout is the product site. Archline Labs remains the home for the complete guides, calculators, and research.
- 01Read on Archline Labs
Norwegian 4x4, explained
The full protocol, pacing, frequency, and research context.
- 02Read on Archline Labs
What VO₂ max training asks of you
Understand intensity, heart-rate lag, and why four minutes matters.
- 03Read on Archline Labs
Find your heart-rate targets
Learn how the 85–95% work range and active recovery fit the session.
- 04Read on Archline Labs
Take the 4×4 to the treadmill
Choose speed and incline without chasing one universal pace.
- 05Read on Archline Labs
Use the free heart-rate calculator
Get your targets before your first guided session.
FAQ
Questions before
your first interval.
What is Norwegian 4x4?
The classic session uses four 4-minute hard intervals with 3-minute active recoveries, plus warmup and cooldown. Ramp4x4 sets up the full session and guides each phase.
What heart rate should I target?
The commonly used work target is 85–95% of your maximum heart rate. Heart rate rises gradually, so use it with effort and pacing rather than treating the first minute as pass or fail.
Can I use a treadmill, bike, elliptical, or run outdoors?
Yes. The session is based on time and effort, so you can use the cardio mode that lets you reach and control the hard intervals safely.
Do I need an Apple Watch?
Apple Watch is the intended wrist experience. Ramp4x4 can also use a compatible external Bluetooth chest strap with iPhone, but the Watch provides wrist haptics, live guidance, and on-watch controls.
How often should I do the workout?
Many training plans use two sessions per week, with recovery between them. Your experience, health, and other training matter, so build up gradually.
Is this medical advice?
No. Ramp4x4 is a training tool, and this site provides general educational information. Talk with a qualified clinician before near-maximal exercise if you have a heart concern or other medical risk.
General training information only. For the full protocol and research context, read the Archline Labs guide.
Your next four intervals
are already set up.
Start the complete guided Norwegian 4x4 on iPhone and Apple Watch.