These workouts will positively benefit you in your uphill pursuits. They’ll build aerobic power, specific leg muscular endurance and maximally work the ventilatory muscles. This can be great to use in he base period for a well trained athlete. With a 5:40 mile you qualify as well trained. How much and often you do these depends on what you goals are and where you are in your training cycle. If mountains (mountain running, alpinism, skimo etc) are your main goal then at some point you’ll want to transition these high intensity workouts to more sport specificity. For skimo and running this will mean running uphill. For mountaineering/alpinism it will mean steep hiking (20-50%+ grade) with a heavy pack. I hope this helps.