Norwegian 4x4 Protocol App: Transform Your Fitness
Download the official app and master the proven 4x4 HIIT method. Boost VO2 max with guided intervals, heart rate tracking, and science-backed training — all in a structured 38-minute workout.
Download the official app and master the proven 4x4 HIIT method. Boost VO2 max with guided intervals, heart rate tracking, and science-backed training — all in a structured 38-minute workout.
with Dr. Rhonda Patrick, Ph.D.
Discussing evidence-based protocols for longevity, heart health, and fitness optimization — validating the scientific foundation behind this HIIT method.
A groundbreaking high-intensity interval training (HIIT) method designed to maximize cardiovascular health and endurance. Four intense four-minute intervals at 90–95% of your maximum heart rate, each followed by a three-minute active recovery. Backed by Norwegian exercise science, the protocol is renowned for significantly boosting VO2 max — and breaking through fitness plateaus that traditional routines cannot touch.
Follow this sequence for a complete 38-minute session:
Light cardio
5 min90–95% HRmax
4 min60–70% HRmax
3 min90–95% HRmax
4 min60–70% HRmax
3 min90–95% HRmax
4 min60–70% HRmax
3 min90–95% HRmax
4 min60–70% HRmax
3 minLight cardio
5 minTotal time: 38 minutes (warm-up, 4 intervals with recoveries, and cool-down)
Estimate your maximum heart rate based on age, weight, and height. Knowing your HRmax is essential for effective interval training.
Calculate Your HRmaxStep-by-step guide to your first workout — guided audio cues, visual timers, and progress tracking built for the 4x4 protocol.
See How It WorksScience-backed benefits that make this HIIT method superior to traditional cardio:
Significantly increases maximum oxygen consumption — the gold standard for cardiovascular fitness.
Complete results in 38 minutes, including warm-up, intervals, recoveries, and cool-down.
Creates an afterburn effect (EPOC) that continues burning calories for hours after your workout.
Builds mental resilience and discipline through challenging high-intensity intervals.
Adaptable to running, cycling, rowing, or any cardio activity that suits your preference.
Backed by extensive research from Norwegian exercise scientists and cardiologists.
Download our comprehensive 30+ page PDF with detailed training plans, heart rate zones, beginner progressions, and expert tips to master the protocol.
Watch our demo to see how easy it is to start your first 4x4 workout
Join thousands who transformed their fitness with our app
"This app transformed my workouts and my endurance has never been better! Great integration with Apple Health."
"I love the structured intervals and easy-to-follow color-coded instructions for the 4x4 workout."
"The best HIIT app I've ever used, designed explicitly for 4x4 intervals. It's a game-changer!"
"This app helped me break through my fitness plateau. Highly recommended!"
Join thousands of users who have improved their cardiovascular health. Download the official app and start your first 38-minute workout today.