Strava

Did you read the article? His point is that if you want to increase your fitness the key is not to add in loads of middling intensity work but to add in focussed high intensity stuff.

These moderate paced rides that are “kinda hard” are the most common form of junk miles. These rides are hard enough to make you feel like you’re working, but easy enough that you don’t feel the urge to vomit. In other words, they’re comfortably painful.
... ?