What's the difference between a sprint and a workout?
A lot of easy cardio at 55-75% is healthy. 5-10 minutes of sprinting at 95-100% is healthy.
However, how much and of what intensity should a workout be? As far as I've read, these [URL="http://www.marksdailyapple.com/primal-blueprint-fitness/workout-of-the-week-archive/#axzz2Sj55v05S"]workouts[/URL] are somewhat intense and last 10-45 minutes.
But, isn't that too (or not enough) intense and too long? Isn't that some form of high intensity dangerous cardio?