I am not a runner. Most of my experiences have been short bursts of pure speed but no real endurance. I’ve attempted to change this as I’ve gotten older these past few years but never stuck with it.
The problem has been my lungs and my knees. After a lot of wear and tear on my knees from high school football, the impact on my feet from running is a horrible experience.
I’ve reduced a lot of impact and injury thanks to good shoes and running on trails instead of pavement.
Still not sure how to break the 5-mile endurance barrier. At my best I’ve managed maybe 2.5 miles non-stop.