What's Better: HIIT Cardio or Steady State Cardio?
By now I’m sure most of you have heard of High Intensity Interval Training, also known as HIIT Cardio, but how does HIIT compare to doing traditional steady state cardio?
Just so we’re all on the same page, HIIT is a form of exercise that involves a work period, where you do a set of exercise as hard/fast as you can (such as a sprint), then follow up with a recovery period of light exercise and then repeat (such as walking slowly). On the other hand, steady state cardio is performing cardio without changing intensity. Examples of this are jogging, walking on a treadmill, using a stair climber, etc.
Fortunately, there have been countless studies looking at the benefits of HIIT cardio in comparison to steady state cardio, and the results are pretty amazing!
One study by Trapp et al. (2008) compared the effects of 20 minutes of HIIT cardio vs 40 min of steady state cardio on fat loss. The study lasted 15 weeks and found that the group performing HIIT had 11.2% greater fat loss! More specifically, the HIIT group decreased abdominal fat by 9.5%. These are awesome results considering the HIIT group exercise sessions were half the time as the steady state (20 min vs 40 min) and the HIIT group was actually resting during the majority of the session. What this study shows is that you can actually burn more fat from HIIT cardio in less than half the time of doing steady state cardio.
Another study done by Scribbans et al. (2014) compared only 4 minutes of HIIT to 30 minutes of steady state and found similar improvements in exercise capacity, with greater increases in the HIIT group! Improvements in exercise capacity means you can train harder and longer, ultimately allowing you to burn more calories! This is yet another study showing greater benefits of HIIT cardio in less than half the time of doing steady state cardio.
Additionally, HIIT cardio has even been shown to suppress appetite. A study done by Holliday et al. (2017) looked at the effects of four 30 second sprints compared to a group that was at rest (this study didn’t compare HIIT vs steady state). What the study found was that subjects reported a significant decrease in feelings of hunger after the exercise session. These results were even accompanied by a suppression of hormones related to appetite control. Ghrelin, which is a hormone that causes you to feel hungry, was decreased by 64% and remained lowered for 2 hours! Another study done by Deighton et al. (2013) found that ghrelin was decreased for up to 6 hours after a HIIT cardio workout. What these studies show is that HIIT can have a positive impact on appetite control, ultimately aiding in fat loss!
Another benefit of HIIT is that it can increase glycogen storage in your muscles. Carbs serve as the main energy source for intense training and they are stored in the form of muscle glycogen. Carbs as muscle glycogen can be quickly used by working muscles. A Study done by Burgomaster et al. (2006) showed that 3 sessions per week of HIIT cardio were able to increase glycogen storage by 50% in the test subjects! This can be extremely beneficial because it essentially increases the energy storage in your muscles, which means you can train harder without getting fatigued!
Now that you know some of the awesome benefits of HIIT cardio, especially in comparison to steady state let’s go over how you can start implementing it.
HIIT is most commonly done on cardio machines but can also be applied to plyometric/conditioning type exercises as well. As far as the appropriate intervals to use I always recommend doing a 1:3 work to recovery ratio. For example if you did a 15 second sprint you would follow up with a 45 second rest period before doing another sprint. So in other words, you want to rest longer than the spring interval. The reason for this is because in order to burn the most calories you want to be able to exercise at the highest intensity. Exercising at your highest intensity means you are able to perform at your absolute highest capacity. In order to do this you need to ensure proper recovery in between sprints/work intervals. If your rest period is too short you aren’t allowing yourself to recover, which means your next sprint will be at a lower intensity due to being fatigued. So make sure you are getting enough rest in between sprints so you can keep pushing hard! Sometimes I’ll even recommend clients to skip one sprint interval if they get too fatigued part way through the session so that they will be less fatigued for the next sprint.
As for how frequently and how long to perform HIIT cardio I usually recommend around 10-20 minutes 3-4x a week, but this will vary depending on individual goals and activity level of each person.
My Favorite type of HIIT cardio is on the stationary bike but as I mentioned above, it doesn’t need to be done on traditional cardio machines! You can do sprints outside, jump squats, battle ropes, sled pushes, rowing machine, tire flips, and kettle bell swings, just to name a few.
And feel free to switch it up with different exercises in the same session. For example you could do jump squats for 15-20 seconds, rest for 45-60 seconds, then do battle ropes for 15-20 seconds, rest, then kettlebell swings for 15-20 seconds, rest, then repeat!
If your goal is fat loss then I highly recommend incorporating HIIT cardio a few times a week into your routine. With so many benefits it will help you maximize your workouts and help you achieve your dream body!