A Short Guide To High Intensity Interval Training (aka HIIT)

Filed under Exercise and Fitness
interval training HIIT

Have you considered High-Intensity Interval Training as a way to burn calories as part of the Flexible Diet?

For years I thought cardio was the holy grail of fat loss.

Just simply go run a 5k, go for a bike ride or do a group fitness class and you were that much closer to a 6-pack. Skip those things and it was your funeral (…maybe literally).

While I now feel more educated and definitely see the great benefits of cardio, my views have changed.

I’ve found cardio, of any kind, is not a necessity of weight loss but rather a tool. Doing cardio is great for cardiovascular health but in terms of weight loss, it is simply a way of achieving a calorie deficit, which is the key to losing weight.

Cardio for weight loss is typically only as useful as the number of calories it burns.

If on Monday you go on the stairmaster for 30 mins and burn 360 calories and then on Tuesday you do 45 mins of running and burn 550 calories, which day was more effective? Typically, it’s the day you burnt the most calories.

What is High-Intensity Interval Training or HIIT?

Simply put, interval training is physical training consisting of alternating periods of high and low-intensity activity.

HIIT (high-intensity-interval-training) seems to be taking the world by storm as a more effective and efficient alternative to the sometimes boring and time-hungry steady-state cardio.

With Interval Training, because you’re varying energy output and intensity, you can burn just as much (and sometimes more) calories with a lower time investment than typical cardio. Workout for 60 mins or just 15 mins?

If you choose to have cardio in your fitness routine then I ultimately suggest you do whatever you enjoy the most, because it’ll be the thing you stick with. But I’d also encourage you to give HIIT a try.

There’s nothing quite like getting your butt handed to you by a short, sharp 8-minute workout.


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Examples of Interval Training Workouts

Large infographic of different HIIT workouts
Source: Fix.com

15 – 30 Minute  HIIT Workouts?

There are literally 1000’s of HIIT workouts on YouTube.

  • Some are geared to men.
  • Some are geared to women.
  • Some use weights.
  • Some use bodyweight.
  • Some are adapted for those with injuries or women who are pregnant.

The possibilities are endless and High-Intensity Interval training can give you a great workout in minimal time.

Orange Theory

Orange Theory provides hour-long HIIT sessions with a coach in a class-like setting. It’s great for those that like the motivation a coach can offer as well as support from classmates.

Participants can also get a great burn from Orange Theory, burning 500-900 calories per workout depending on your stats and how hard you go at it.

Orange Theory Centers are found throughout the country.


Crossfit is another type of interval training that has a lot of variation and also has a big strength training component.

Participants work through a Workout of the Day (WOD) consisting of various movements that have varying degrees of intensity.

WOD Example:

  • 30 box jumps
  • 15 clean and jerks, 65 | 95 lb.
  • 30 box jumps
  • 15 clean and jerks, 85 | 135 lb.
  • 30 box jumps
  • 10 clean and jerks, 115 | 185 lb.
  • 30 single-leg squats
  • 10 clean and jerks, 145 | 225 lb.
  • 30 single-leg squats
  • 5 clean and jerks, 175 | 275 lb.
  • 30 single-leg squats
  • 5 clean and jerks, 205 | 315 lb.

CrossFit is huge on peer support and has a strong community focus.

If you’re tired of the same old cardio or the same old gym routine, High-Intensity Interval Training can be a great way to switch things up, while getting a great calorie burn.

Ted Kallmyer is an ISSA certified Specialist in Fitness Nutrition, author, and macros coach. He has helped hundreds of clients reach their body transformation goals.
Updated May 9, 2022


  • Ryan

    My advice to most people is that the core of their training should be full-body weights 3 times a week, with the squat and/or deadlift in each of those sessions. HIIT presents an advantage if cardio is your only form of exercise, but it conflicts with proper lower-body weight training.

    I’ve been adding in low-intensity cardio (on an exercise bike while I play video games or watch stuff). My body’s still adapting to higher durations, but I’ve already pushed my maintenance from ~3100 to ~3400, which lets me enjoy more food and (possibly) get better nutrient partitioning.

    • Dan Bolton

      Thanks for sharing, Ryan!
      Curious as to your thoughts on how HIIT conflicts with lower-body weight training?

      • Ryan

        It’s hard to recover from and will conflict with your strength maintenance/progression on lower-body lifts, especially if not programmed intelligently. If you’re squatting and/or deadlifting 3+ times a week (which you generally should be), HIIT is redundant.

  • spectra311

    I like it for days when I don’t have the time to fit in a longer workout because I feel like I am getting my heart rate up high enough to get some results. I do Tabata intervals where I do plank jumps for 20 seconds alternating with 20 seconds of weighted squats and 20 seconds of jump rope. I repeat until my workout’s over–around 15 minutes or so. I’m always totally winded after that’s over.

    • JamesF

      What’s a plank jump?

      • spectra311

        You get into plank position on your hands (not your forearms) and start with your legs together. Keep your arms still but jump with your legs and spread them out to the sides and land with your legs apart. Then jump again and pull them back together. It’s kind of like doing jumping jacks in plank pose. It’s also a serious workout.

        • Dan Bolton

          It sounds serious.. gotta give it a try sometime 🙂

  • Daniel Wagle

    My experience is that YES, high intensity does help, but NO, it does not burn that many calories if I shorten my workout considerably. In five minutes of high intensity exercise a person might burn about 100-200 calories- that is a lot for 5 minutes, but it is not a lot of calories. Running 10 miles will always burn more calories than running 2 miles, no matter how fast the 2 miles were run. I found out on my bicycle that I controlled my weight better if I increased my distance than by increasing my speed. Both on the shorter and the longer rides, I did include the very steep hill that leaves me a little breathless. The longer ride added some extra hills as well. On the other hand, my experience is that leisurely walking is not that effective for weight loss, even if it is done for a long time. A two hour leisurely walk at 2mph might not even burn as many as 400 calories. A more intense run or bike ride can burn from about 1400-2000 calories in two hours. . So YES, intensity, but duration and distance still count.