What is Peak Fitness?

A continuing exploration

As training for the Headlands 50K enters its final stage, I can sense significant aerobic changes taking place. Runs that felt long and arduous earlier in the training cycle now seem short and enjoyable. Workouts that looked impossible on paper back in the spring feel manageable. 

That tells me I’m approaching a state of peak fitness; a somewhat nebulous concept that nevertheless feels as real as breathing. In a sense, peak fitness is like a superpower I never knew I had. A potent blend of cardiovascular capacity and supreme confidence that is as intoxicating as any drug on the planet. 

My feelings of athletic apogee – at least my version – are validated by several bits of raw data including longer runs, faster paces, and a heart rate that has remained remarkably steady through even the most challenging workouts. It’s tempting to want to stay in this state forever, but peak fitness has an expiration date.