By 50, the male body hits brutal degradation metrics: testosterone drops 30%, arterial stiffness climbs 30%, bone density falls 10%, muscle mass shrinks 10%, and half of all men deal with prostate enlargement.

Bryan Johnson's protocol to counter this:
• 4 hours heavy lifting per week
• 3 hours zone 2 cardio
• 45 min HIIT
• 2 hours sauna
• 8 hours sleep nightly

This isn't anti-aging hype, it's a measured intervention stack targeting the specific failure modes of male physiology post-40. The volume here is higher than most casual fitness advice but aligns with what actual longevity research suggests for maintaining physiological resilience.