4x4 Intervals
Forty minutes a week that move endurance the most
Who it’s for
Have a walking or running base, need a real jump in endurance.
How it works
Four 4-minute intervals at 90–95% HRmax with three minutes of light work in between. In a head-to-head comparison with continuous and threshold work at equal volume, only intervals yielded gains: +7.2% vs. nearly zero. Stroke volume increased by about 10%. 8-minute intervals work even better (+11.4%) and feel easier.
Weekly layout
How load increases
First master four 4-minute intervals, then progress to four 8-minute intervals at a slightly lower intensity. What matters isn't peak heart rate, but total time spent above 90%.
Deload
Every fourth week: one interval day instead of two.
Tailored to your health
Some exercises will be automatically swapped or removed based on your health profile:
Programs are for guidance only and are not medical advice. Consult a doctor if you have health conditions.
© 2026 ИП Круглов · БИН 920203350537