F*^k Aging!

Strength After 40

Heart Rate Zone Calculator

Karvonen-method training zones from age and resting heart rate, including Zone 2 for aerobic base work.

Measure first thing in the morning, before getting out of bed, for a few days and average it.

Uses the Karvonen method with an age-predicted max heart rate (220 − age), which is itself a rough population estimate — individual max heart rate can vary by 10–20 bpm either way. For informational purposes only, not medical advice. Consult a clinician before starting a new training program, especially with any cardiac history.