Both of you are kind of right. It’s still an insane feat of endurance but averaging an 18 minute mile is pretty damn slow and likely zone 2-3 even in rugged terrain for an athlete like her.
High intensity isn’t just a generalized term but specific to heart rate, lactate buildup, and anaerobic states.
The more you spread that over the day the better. Higher intensity will kill you, you want lower intensity.
I’m not sure two marathons per day can be qualified of lower intensity.
Both of you are kind of right. It’s still an insane feat of endurance but averaging an 18 minute mile is pretty damn slow and likely zone 2-3 even in rugged terrain for an athlete like her.
High intensity isn’t just a generalized term but specific to heart rate, lactate buildup, and anaerobic states.
A friend of mine regularly runs trail ultra-marathons. She calls it “assisted hiking”.