Exercise
The closest thing to a magic pill. If exercise were a drug, it would be the most prescribed medicine in history. It improves virtually every health marker, builds new mitochondria, grows new brain cells, and extends lifespan. Yet most people don't get enough.
What Exercise Does
Mitochondrial Biogenesis
Grows new mitochondria. Exercise is the strongest signal for PGC-1α and mitochondrial production.
Brain Growth (BDNF)
Exercise is the most powerful natural BDNF booster. Grows new neurons, improves memory.
Insulin Sensitivity
Muscles become glucose sponges. Effect lasts 24-48 hours. Prevents/reverses type 2 diabetes.
Autophagy Activation
Exercise triggers cellular cleanup. Removes damaged proteins and organelles. Anti-aging effect.
Cardiovascular Fitness
Strengthens heart, improves VO₂max. Single strongest predictor of all-cause mortality.
Mood & Mental Health
As effective as antidepressants for mild-moderate depression. Reduces anxiety. Improves sleep.
Types of Exercise
Aerobic / Cardio
- Zone 2: Conversational pace. Builds mitochondria. 80% of training volume.
- HIIT: High intensity intervals. VO₂max improvement. 1-2x/week.
- Walking: Underrated. 10K steps = significant health benefits.
- Benefits: Heart, lungs, blood vessels, brain, metabolism.
Resistance / Strength
- Muscle building: Preserves muscle mass with aging (sarcopenia prevention).
- Bone density: Load-bearing exercise strengthens bones.
- Metabolic rate: Muscle is metabolically active. Burns calories at rest.
- Minimum: 2x/week hitting major muscle groups.
Zone 2 Training
The sweet spot for metabolic health and mitochondrial building:
What It Is
60-70% max heart rate. Can hold a conversation but would prefer not to. Nose breathing possible.
Mitochondria
Builds type 1 (slow-twitch) mitochondria. Improves fat oxidation. Expands metabolic capacity.
Duration
Minimum 45 min sessions. Ideal 3-4 hours/week total. Can be split across sessions.
Practical Recommendations
Weekly Minimum
150 min moderate cardio OR 75 min vigorous. Plus 2x strength training. This is minimum, not optimal.
Ideal Distribution
3-4 hr Zone 2, 1x HIIT, 2-3x resistance. Daily walking. Mobility/flexibility work.
Start Where You Are
10 min walk is infinitely better than no walk. Progress gradually. Consistency beats intensity.
Recovery Matters
Adaptations happen during recovery. Sleep is critical. Don't overtrain. Listen to your body.