From a medical research standpoint, 2007 was the year of interval training. In January, The University of New South Wales released a study (note released not published) that showed that high-intensity interval training was more effective than continuous moderate exercise at reducing fat. The study showed the benefits using women exercising with alternating sprints and moderate speed on a stationary bike for 20 minutes versus continuous moderate biking for 40 minutes. Over 15 weeks, the interval group (sprints and moderate biking) lost three times as much fat as the traditional exercise group. That’s contrary to traditional exercise thinking since more fat was lost with half of the total exercise time. Due to their rapid news cycle, SELF magazine just now noticed .

In the peer-reviewed literature, the folks at Shinshu University Graduate School of Medicine got down and dirty with the statistical measurements . They found that by alternating high intensity walking and moderate intensity walking in three minute intervals caused more improvement in blood pressure, a greater increase in exercise capacity and a greater increase in leg strength than continuous moderate exercise.

Canadian researchers got down in the enzymes and metabolic change and showed definitively that interval training produces significant improvement in fat oxidation.

So what to do with this information? Ultimately any aerobic exercise is good. Interval training is faster and better. Runners and others have known this for a long time. I remember years ago that high school coaches had their athletes doing wind sprints . You can modify your existing routines a number of ways. Add super fast walking at intervals to a walking routine, bike sprints followed by moderate biking. That kind of thing. Some exercise machines even have these kinds of routines built into their programming. I’ve been using a LifeCycle for years that has a "hill" routine that is essentially interval training. For the workout video set, there’s 10 Minute Trainer from Beachbody. I’ve been using this routine for 3 weeks and frankly, as someone who is fairly fit have been surprised how much difference tightening up the routine into a highly engineered interval plan makes.

No matter the path you choose, interval training really needs to become part of the plan. It’s definitely easier to start with long moderate activity routines but the real benefits in fitness and time saved come with interval training.