Story perspectives

Norwegian 4x4 Workout Boosts Fitness, Inspires New Program

10/16/2025

Summary

Story summary

The Norwegian 4x4 workout method, developed by researchers at the Norwegian University of Science and Technology, is gaining popularity for cardiovascular fitness.
The method uses four-minute intervals at 85–95% of maximum heart rate with three minutes of recovery.
It has shown significant improvements in VO2 max, linked to better endurance.
Tony Horton has launched The Power of 4 with BODi, a program blending strength, nutrition, and mindfulness for long-term vitality.

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Story summary

The Norwegian 4x4 workout method, developed by researchers at the Norwegian University of Science and Technology, is gaining popularity for cardiovascular fitness.
The method uses four-minute intervals at 85–95% of maximum heart rate with three minutes of recovery.
It has shown significant improvements in VO2 max, linked to better endurance.
Tony Horton has launched The Power of 4 with BODi, a program blending strength, nutrition, and mindfulness for long-term vitality.