Here's what has changed, and what has been learned.Read article
Walk in to any gym today and you’ll see cardio row being used the same way it was in 1980. Treadmills set to 3.5 mph, maybe with a slight incline, timers approaching 45 minutes with nary a sweat broken on the brow of any of these willful walkers.
Despite the overwhelming evidence in favor of high-intensity interval training for fat-burning, folks still choose to “speed” walk for longer bouts with as much regularity as ever. It’s easier, sure, but those who truly want to get lean may want to consider at least occasionally cranking up the intensity. Still not convinced? We’ll let the research do the talking.
In 1994, Angelo Tremblay and some of his colleagues at the Physical Activities Science Laboratory at Laval University in Canada tested the long-held belief amongst most exercise and medical professionals that long, slow cardio at a low intensity is superior for fat loss. In fact, they compared the impact of moderate- and low-intensity to high intensity interval training in hopes of finding what was superior for fat loss.
One group did 20 weeks of endurance training while the other group did 15 weeks of high intensity interval training. The cost of total energy expenditure was much higher in the endurance-training group than the interval group.
Additionally, Tremblay and his associates found that the endurance group burned nearly twice the amount of calories during training than the interval group. This is where things got weird: skin fold measurements showed the interval training group lost nine times more body fat than the endurance-training group. The research showed that the interval trainees got nine times the fat loss for every calorie burned during training.
The researchers from Laval University found that metabolic adaptations that were a result of interval training may lead to enhanced lipid utilization post exercise, effectively accelerating fat loss.
Fat is the fuel for lower-intensity exercise while carbohydrates fuel fhigher-intensity intervals. While excess dietary fat can cause unwanted fat gain, so can excess in carbohydrates. This study confirms the need to look beyond the scope of what macronutrient is fueling the workout, or how many calories are burned during the workout. We must also look at what happens post-workout.
Intervals stimulate your post-workout metabolism much greater than long, slow cardio. Additionally, studies have shown intense intervals produce increased anabolic hormones post-workout.
This is why interval training has so many die-hard advocates and supporters. Science confirms interval training is highly effective for fat loss. Looking for a quick example? Check out the physiques of marathoners versus sprinters.
Lucky for you iron lovers, who prefer to spend as little time as possible on the treadmill, HIIT principles go well beyond cardio row. Izumi Tabata has conducted research for the National Institute of Fitness and Sports in Tokyo, Japan. In terms of aerobic benefits, Tabata demonstrated that a program of 20 seconds of all-out cycling followed by 10 seconds of low intensity cycling for four minutes was as beneficial as 45 minutes of long, slow cardio.
Tabata training is now a popular form of interval training that includes performing an activity all-out for 20 seconds, followed by a 10 second rest interval. Some popular methods of Tabata training include jumping rope, burpees, and kettlebell swings, along with many others. The protocols can be applied to practically any resistance exercise, allowing you to increase your metabolism and get a great muscle-building pump in the process. Numerous studies also confirm the effectiveness of interval training enhancing aerobic capacity.
Elite distance runners are far from physical specimens. On the contrary, some often appear sickly and emaciated. That’s because excessive aerobic training can decrease testosterone production, decrease immune system efficiency, increase cortisol production and put a serious halt to any sort of strength or muscle gains.
Steady-state training does hold some advantages.
If you’re looking to augment your existing training program, lower-intensity, steady-state cardio definitely has a place. But it shouldn’t be the main facet of your fat-fighting efforts.
Intense interval training properly programmed can expedite fat loss. However, similar to intense weight training, your body and central nervous system will need time to recover from the demands of interval training. Two days a week of intense interval training is a great place to start. You can use “off days” to get in some leisurely walking – either outdoors or on a treadmill – to assist in recovery.
Research varies on the ideal HIIT interval ratio but you can start with a 1:3 work-to-rest ratio (say, 20 seconds of work and 40 seconds of rest) and increase work while decreasing rest as you adapt.
While fat gain is predominantly the consequence of decisions made in the kitchen, interval training can be the final push to plow through a fat loss stalemate.
Josh Bryant, MFS, CSCS, PES, is the owner of JoshStrength.com and co-author (with Adam benShea) of the Amazon No. 1 seller Jailhouse Strong. He is a strength coach at Metroflex Gym in Arlington, Texas, and holds 12 world records in powerlifting. You can connect with him on Twitter and Facebook or visit his website at www.joshstrength.com