Zone 2 Cardio Training
ExerciseBy Peter Attia
Low-intensity aerobic exercise to build mitochondrial density and metabolic flexibility.
Clear, actionable protocols you can implement today—no PhD required. Each one includes evidence ratings, time commitments, and practical steps for adults 50+.
When experts recommend different approaches, we help you understand why—and which might work better for your situation, schedule, and goals.
Compare ProtocolsDisclaimer: The protocols on this site are for educational purposes only and are not medical advice. Evidence levels vary—some protocols are based on strong clinical research while others reflect expert opinion. Always consult with a qualified healthcare provider before starting any new health protocol, especially if you are over 50, take medications, or have existing health conditions.