October Is for Interval Workouts
by Beth Skwarecki on Vitals, shared by Beth Skwarecki from Lifehacker on (#4RTSK)

It's time to kick up the cardio a notch and do some intervals this October! (Intervaltober? HIITober? Okay, never mind.) There are lots of ways to do intervals, and they don't all have to feel like you're dying, so let's explore the possibilities.