I’m 59, still running long trail days in the Black Hills, and I’ve stopped pretending I can out-sprint aging. I’m training for durability now—being “less slow” later in the run and later in life. That means Zone 1–2, time on feet, hiking on purpose, and caring more about aerobic decoupling and TSS than braggy splits. The goal is simple: move well when I’m tired, stack weeks without breaking, and keep saying yes to long days outside for as many years as I can. I wrote about what that actually looks like here.