Someone once told me that "the future is already here, it just takes 5 or so years before it is recognized".<p>This is not news to most serious athletes or trainers. I'd go so far as to say this is really par for the course and old-hat at this point. Unless you are an endurance athlete, no one is advocating long durations anymore<i>. And, particularly for the average person, this is a much more manageable and, frankly, approachable solution.<p>The average person would get much, much more out of tabata kettlebell swings, tabata mountain climbers tabata jump rope than running 6 miles.<p></i> The exception I'm thinking of here is if you are a serious body builder, you might be doing long duration walks (30-60 minutes) as your cardio. These people are trying to spare as much muscle as possible while reducing bodyfat to crazy low levels. Some BB like to stay away from intense, short duration cardio b/c they think it might cut into some of their muscle gains. I can't say I've seen science support this, but this is an exception I can think of.