Which is better: Steady State Cardio vs. HIIT Cardio, or High Intensity Interval Training Cardio? Which is more effective for fitness? How about for fat loss?? Well, as all things related to fitness, it depends.
The Gibala Study out of McMaster University compared 20 minutes of HIIT cardio (30 sec sprint, 4 minute rest) with 90-120 minutes of steady state cardio training in a prespecified target heart rate zone, and subjects got the same enhancement of oxygen utilization from both programs. The HIIT protocol actually only consisted of 2 minutes and 30 seconds of actual work, which was pretty amazing.
Another study, famously known as the Tabata study, (if you ever hear of people doing Tabata’s, this study is where they got it from), compared 70% VO2 max endurance training (moderately intense), with a HIIT protocol of 20 seconds:10 seconds work to rest ratio, done at 170% (ridiculously intense!) of VO2 max, for 7 to 8 sets (each set consisting of 20 second balls to the wall sprint, followed by 10 seconds of complete rest). The results showed that the Tabata protocol (20s:10s) was far more effective at improving anaerobic energy systems and VO2 max than the steady state program.
Not only that, but studies show that HIIT training recruits more fast twitch Type II muscle fibers (explosive, high activation, phasic), which is awesome for individuals trying to improve their bodies ability to utilize oxygen WHILE ALSO partaking in a strength and/or power resistance-based training program. This is important because steady state cardio recruits mainly Type I muscle fibers (slow, cyclical, repetitive, lower activation) which cause the nervous system to NOT stimulate muscle fibers to change their phenotype to a Type II composition. Thus, in laymens terms, when cojoining a steady state cardio exercise program with a strength/power resistance program, the cardio program may be deleterious to the body’s response to the resistance training program, and vice/versa.
Even from a caloric standpoint, consider the following:
a 140 lb person will burn approximately 100 cal/mile, if walking. Running at, for example 8mph, clearly a more “intense” form of cardio when compared to walking, will burn ~1.3x as much calories as walking (4 mph vs. 8 mph). This means that a runner can burn 130 calories/mile running at 8mph (it would take approximately ~7:30 min to complete a mile running at 8mph). Compare this with walking a mile at 4mph, which would take you approx. 15 minutes might I add, and you burn fewer calories to boot. That equals out to around 4 calories/minute, whereas the individual who is running burns approx. 11.5 calories/minute. Thus, all other variables equal, my point is is that work completed at a higher intensity will equal greater energy (calorie) expenditure per minute. Hope I didn’t lose you there. In case I did, let the Spirit of Radio rekindle your focus:
Rush = excellence. nuff said.
Is it true?
Anyway, so far, it sounds like HIIT cardio is the winner right? burn a ton more calories in a shorter period of time sounds pretty sweet to me. But lets not throw Steady state by the wayside. In my opinion, there are good reasons for steady state cardio, as long as the individual understands those reasons. For starters, its great for lowering your resting heart rate. Studies show that when individuals engage in target heart rate zone training, primarily in the 50-60% VO2 max range, it will have a positive effect on the individuals ability to reducing resting heart rate. Also, proponents of steady state cardio training claim that it is excellent for reducing stress, relaxing, and clearing your mind, because of the nature of the activity: its cyclical, repetitive, predictable, and at a lower intensity. Also, not everyone has the ability to train at such high intensities, such as individuals with pre-existing heart conditions, so just the fact that steady state cardio STRENGTHENS your heart and systemic circulation is convincing enough for the individual to know that steady state DOES serve a purpose, especially with special populations. Not to mention that bodybuilders have been utilizing this technique for years to shred fat and get to competition physique. I’ll talk more about this later though, there’s a catch with this that i’ll explain in the next post.