In this episode, Dave Barney and Luke Olson dive into the connections between physical activity and mental health. Topics covered:

• Movement as a "state change tool" for your nervous system
• BDNF: the brain protein scientists call "fertilizer for the brain"
• How exercise reduces inflammation and regulates stress response
• The minimum effective dose: why 10 minutes matters
• Walking, resistance training, yoga, and cardio — different mental effects
• Measuring mental fitness progress (not weight or appearance)
• How movement strengthens all three pillars of mental fitness
• Winston Churchill's walking habit for managing depression

Key research cited: 2024 BMJ systematic review finding exercise effective for depression symptoms. WHO recommends 150-300 minutes of moderate activity per week.

The takeaway: A 10-minute walk after lunch, ideally in sunlight, is the minimum viable mental fitness habit.