Norwegian HIIT starting at 30 seconds, scaling to the full 4×4 protocol
AI-powered personal training and nutrition planning
Stage
Not given
Startup
Founded
Not given
2026
Based in
PL
SI
Pricing model
Free
Freemium
Pricing
Not given
Free: €0 forever with personalized calorie and macro targets, sample workout and meal plan, and full exercise library. Pro: €14.99/month (14 days free trial) with weekly adaptive workout plans, daily meal plans with carb cycling, and progress tracking. Coach: €29.99/month with all Pro features plus
Key features
Progressive on-ramp starting at 30-second intervals
Voice-guided coaching throughout entire session
Lock Screen and Dynamic Island display (iOS 17+)
Works with screen locked and music playing
Available in four languages
Personalized heart-rate zones computed from max heart rate
Native Apple Watch Workout app integration
Adaptive level progression based on recovery data
No account, no ads, no tracking
Personalized workout programs by goal and fitness level
Smart meal plans with exact macros and calorie targets
Carb cycling matched to training days
500+ illustrated exercise animations with step-by-step guidance
Weekly progress tracking and plan adaptation
24/7 AI coach available in Coach tier
Wearable and smart scale integrations coming soon
Equipment-specific plan adaptation
Body balance tracking and 2fit4u Score
Weekly photo check-ins with AI feedback in Coach tier
What makes it different
Structured progressive on-ramp that no other 4×4 resource offers
Never forced progression: holds levels based on recovery data and never uses shame mechanics
Privacy by design with no account or tracking required
Works completely with screen locked and music playing through voice cues
Based on published scientific research including Mifflin-St Jeor, ISSN, and evidence-based training standards
Developed by someone with 35+ years of personal training experience, not marketers
Adapts weekly to your logged progress instead of using generic templates
Personalization around your actual equipment, schedule, and preferences
Forever free tier with full exercise library and personalized calorie targets
Crescendo 4×4
2fit4u