What’s the best cardio workout? Is it different for each individual? Both are common questions, and we decided to dig into the data.
This in-depth post summarizes an experiment we conducted with a variety of workouts – from free YouTube workouts to your standard gym equipment to professionally designed routines.
It was interesting to learn that for us, the best cardio workouts are 60-90% more effective for weight loss than the worst.
In my case, if I did the worst workout instead of the best for a year, I would leave 23 pounds of weight loss on the table. Or, if I wanted to lose 23 pounds, it would take me 78 additional hours or 3.25 days!!
The experiment opened our eyes to the importance of working out smart. So, you want to know what’s the best cardio workout? Let’s dive into the experiment.
what is the best cardio workout?
Alex and I have always been fans of working out together. There are many incredible benefits of working out with your partner.
When we started sweating it out together, it quickly became clear that our bodies responded very differently to different forms of exercise.
It was eye opening to see Alex’s heart rate peaking during a run when I needed to do a high intensity workout to see the same result.
Since we’re engineers (and control freaks) we wanted to collect the data and make sure that we were doing the most effective cardio workouts.
Afterall, cardio is not that fun, so we wanted to make sure we were maximizing our results in the least amount of time.
So, we designed a cardio experiment. In this article, we’ll share the experiment details, results, and takeaways. Keep in mind, the experimental results are our own. Yours would be different.
Therefore, we share all of the experimental details so that you can replicate it and determine which form of cardio is best for your body.
The Best Cardio Experiment
In this section, we will outline (in great detail) the details of our experiment.
We discuss the goal of the experiment, our hypothesis, the workouts we did, and the variables that we controlled to get accurate results.
Cardio Experiment Goal
I have always been a fan of high-intensity cardio workouts. I started running at a young age, ran cross-country competitively, and played soccer year-round throughout high school.
Alex has also been a lifelong fan of cardio workouts, but she refers to herself as a “one-speed pony.” She has never liked the high-intensity workouts as much as I do and prefers running, swimming, and lifting weights.
Workout preferences aside, the purpose of this experiment was to identify the best, most effective cardio workout. Since we’ll be using heart rate analysis, our definition of “the best, most effective workout” is the workout that burns the most calories.
We will measure calories burned during the 20-minute workouts and for 60 minutes immediately after for the “afterburn effect.” We understand that there is more to a workout than just calories burned, but for experimental purposes, this was our best metric.
So, based on our experience, what do we think is the best cardio workout? Probably the workout that has the fastest pace, fewest breaks, and engages the most muscle groups, because that will burn the most calories.
“I am confident that the Beachbody On Demand cardio workouts are going to be the best. It is total body, explosive cardio, they are designed by world-renowned trainers and a team of sports scientists, and they include only enough breaks to prevent you from fainting. I think HIIT will take the cake, and I have never been impressed with workouts on YouTube” – Ryan
“Although I love running and enjoy spin classes, I don’t think either will be the best cardio workouts. They don’t engage enough muscle groups, and they are less explosive than High-Intensity Interval Training (HIIT). I know nothing about the YouTube workouts, but I expect some form of HIIT to win.” – Alex
We have experience doing a variety of HIIT workouts and even designed an at-home, total-body HIIT routine for couples.
About The Experiment
This was a highly detailed experiment to determine what the best cardio workout is. We did our best to control all variables from diet to sleep quantity to hydration to alcohol consumption.
We’re all unique individuals, and our results could be different than yours. In this post, you have everything you need to repeat the experiment and find out what is the best cardio workout for you.
If you plan to repeat the experiment, or if you’re just geeks like us, below are the detailed controls and variables. If you’re not, skip down to the results section.
Workouts (20 minutes of each):
- YouTube Cardio 1: Fitness Blender – Fat Burning HIIT Cardio Workout (6.6MM views at the time of post)
- YouTube Cardio 2: POPSUGAR Fitness – Burn Major Calories With This Cardio Workout (2.3 MM views at the time of post)
- Exercise bike (Classic Cardio program – full details in Appendix VI)
- Treadmill (8.5-minute mile)
- Beachbody On Demand (BOD) Cardio 1: Transform :20 Sample Workout
- Beachbody On Demand (BOD) Cardio 2: Insanity Max :30 Cardio Challenge (BOD membership or free trial required)
Note – If there was a warm-up included in the routine, that was skipped. Instead, we followed a consistent warm-up for all workouts summarized in the “Controls” section below.
- Ryan – 30 years old, 175 lbs, 7% Body Fat Composition (collected using this caliper), and intermediate/advanced fitness ability according to our fitness test
- Alex – 30 years old, 105 lbs, 18% Body Fat Composition, and intermediate/advanced fitness ability
Days: One workout a day in randomized order (see Appendix V).
- No alcohol during experiment or two days before the start, although, typically drinking is fine in moderation
- 8-9 hours of sleep tracked using the Pillow app (see sleep data in Appendix III)
- Followed portion control container plan during the experiment (see food details and tracked containers in Appendix IV)
- Morning workouts between 8:30 and 9:30 AM
- No food or supplements between wake and work out
- Ryan – 40 ounces of water between wake and work out
- Alex – 20 ounces of water between wake and work out
- Collect data with Polar H7 HR Monitor during the 20-minute workout – referred to as “the burn”
- Collect data with Polar H7 HR Monitor immediately after the workout for 60 minutes while reading by the pool – referred to as “the afterburn”
- Warm-up for 2.5 minutes (not included in HR data):
- Run in place (30 seconds)
- Jumping jacks (30 seconds)
- Side step twists (30 seconds)
- Stretch (60 seconds)
- No other workouts during the experiment
- No music during workouts
The Best Cardio Experiment Results
The results are in! Based on our analysis, our experimental results are accurate and the data is conclusive. VERY conclusive.
The graphs below illustrate a strong correlation between average heart rate and calorie burn during the workouts.
As shown in the graphs, Ryan burns significantly more calories than Alex during a cardio workout, and Alex tends to maintain a lower average heart rate. See Appendix I for the data tables.
The below graphs show the total calories burned (calories during the burn + the afterburn) as a result of each workout. Both BOD Cardio workouts showed the highest calorie burned during the 60-minute afterburn for both Ryan and Alex.
The regression analysis for both data sets is shown in the below plots. The analysis confirms a nearly perfect (R2 = 1) correlation between average heart rate and calorie burn. Therefore, our experimental results are accurate.
Cardio Experiment Results
If you really want to geek out with us, feel free to read the long version of the results. Otherwise, here is a shorter summary of our findings.
The short version:
So, what’s the best cardio workout for Ryan and Alex?
BOD Cardio 2, Insanity Max:30 Cardio Challenge, was the best cardio work out for both. BOD Cardio 1 was the second-best.
For Ryan, it was 91% more effective than the worst form of cardio, the exercise bike. And for Alex, it was 73% better than her worst cardio workout, the Fitness Blender workout on YouTube.
Let’s translate that data into something more digestible, Chipotle burritos (see what I did there?).
If Ryan did his worst form of cardio instead of his best for one year, he would miss the opportunity to burn an excess of 74 Chipotle burritos in calories. That’s the equivalent of 23 pounds of weight loss.
Similarly, if Alex did the same, she would miss the opportunity to burn an excess of 22 Chipotle burritos in calories. Therefore, she is leaving 7 pounds of weight loss on the table.
Of course, there is no such thing as bad cardio. Just less effective cardio. So, let’s say Ryan loves the exercise bike. That’s fine, but he would need to exercise for an additional 78 hours that year to burn off enough calories to lose 23 pounds. That’s 3.25 days on the bike!
Clearly, there is effective cardio and far less effective cardio. Take the time to find the best cardio workout for you, but when in doubt, HIIT is where it’s at. For more details, our calculations, and the long version, click the toggle below.
The longer version:
For Ryan, BOD Cardio 2, Insanity Max :30, was…
- 11% better than BOD Cardio 1, Transform :20
- 44% better than the treadmill
- 91% better than the exercise bike
- 68% better than YouTube Cardio 2, POPSUGAR Fitness
- 77% better than YouTube Cardio 1, Fitness Blender
For Alex, BOD Cardio 2, Insanity Max :30, was…
- 7% better than BOD Cardio 1, Transform :20
- 13% better than the treadmill
- 30% better than the exercise bike
- 60% better than YouTube Cardio 2, POPSUGAR Fitness
- 73% better than YouTube Cardio 1, Fitness Blender
If Ryan did 20-minutes of BOD Cardio 2, Insanity Max :30, five days a week for one year he would burn 169,780 calories. That’s…
- 16,640 calories, or 15 Chipotle burritos*, more than BOD Cardio 1, Transform:20
- 51,740 calories, or 47 Chipotle burritos, more than the treadmill
- 80,860 calories, or 74 chipotle burritos, more than the exercise bike
- 68,640 calories, or 63 Chipotle burritos, more than YouTube Cardio 2, POPSUGAR Fitness
- 73,840 calories, or 67 Chipotle burritos (that’s 100 lbs), more than YouTube Cardio 1, Fitness Blender
If Alex did 20-minutes of BOD Cardio 2, Insanity Max :30, five days a week for one year she would burn 56,160 calories. That’s…
- 3,900 calories, or 4 Chipotle burritos*, more than BOD Cardio 1, Transform:20
- 6,500 calories, or 6 Chipotle burritos, more than the treadmill
- 13,000 calories, or 12 chipotle burritos, more than the exercise bike
- 21,060 calories, or 19 Chipotle burritos, more than YouTube Cardio 2, POPSUGAR Fitness
- 23,660 calories, or 22 Chipotle burritos, more than YouTube Cardio 1, Fitness Blender
* One Chipotle burrito is 1,095 calories. Flour tortilla, chicken, brown rice, black beans, fajita mix veggies, salsas, cheese and lettuce (no sour cream or guacamole).
Key Takeaways & Conclusions
Clearly, there is such a thing as effective cardio and less effective cardio.
And in our experience, Beachbody On Demand offers the most effective cardio. To work out smarter, we recommend following these tips. Here are our key takeaways from our cardio experiment.
1. Figure out what cardio is best for you
You can only do this by tracking your workouts with your FitBit, Apple Watch, or the highly accurate Polar H7 heart rate monitor.
We used the Polar H7 for accuracy during this experiment, but our Apple Watches are reasonably accurate. We are happy with the series 3 watch for him and for her.
For Ryan, no other form of cardio came close to HIIT, but for Alex, running on the treadmill (8.5-minute mile) was a close runner up.
The exercise bike and YouTube Cardio workouts were poor cardio workouts for both of us (according to the heart rate analysis charts in Appendix II).
The bad cardio workouts are usually slower paced with too many breaks to maintain an elevated heart rate. You’ll know they are bad because they aren’t challenging enough.
And when they are challenging, they continue to work for you even after the workout is over.
Both Ryan and Alex burned more calories during the afterburn (60 minutes after the workouts) with BOD Cardio 1 and 2 workouts (Insanity Max:30 and Transform:20, respectively).
These workouts maintained a high average heart rate (also delivered the highest max heart rates of all workouts) by challenging multiple muscle groups.
Therefore, having total body resistance moves in your cardio routine increases the calories burned in the afterburn. The more with lunges, jumping squats, push-ups, burpees, mountain climbers, and core moves, you can squeeze into your cardio routine, the better.
All the details of this experiment are listed below. Go ahead and repeat it for yourselves. You can do so with a free trial of the Beachbody On Demand workouts.
Update: Since doing this experiment, I trained for and crushed his first marathon (I’d like to thank my coach, Alex). Once I was running outside at a faster pace, I was massively impressed by my heart rate and calorie burn data. It’s likely that the treadmill and 8.5 minute mile pace in this experiment wasn’t challenging enough.
Running changes your body in ways other forms of exercise don’t. We highly recommend running, and while you’re at it, why not a marathon? In this article, we share how to train for a marathon and provide a 3-Month Marathon Training Schedule.
2. Partner up
Let’s face it. Cardio isn’t that fun.
But it can be when you do it as a couple. You gain accountability, push yourselves harder, and boost your attraction to each other. Just to name a few of the benefits of working out as a couple.
Don’t believe us? Recruit your partner and give our couples workout routine as shot.
3. Eat the right amount of calories
Exercise is necessary, but healthy eating is essential. It was important for us to learn that Ryan burns 3X calories compared to Alex while requiring 2X calories from meals.
We know that everybody and every body is different, but this was a significant finding.
After this experiment, we started paying more attention to portioning our meals. This is important because you won’t see results from your cardio if you’re not eating the right amount of fuel.
We share our learnings in our article titled ‘How to Manage Diets as a Couple.‘ If haven’t tracked your calories before, follow the guide in our 30-Day Weight Loss Challenge.
Best Cardio Experiment Notes
In this section, we share our workout summary, day by day. Additionally, we’ll share links to the exact workouts we followed so you can repeat the experiment.
Day 1 – Treadmill
So, what is the best cardio workout?
Today, we started the experiment on the treadmill and ran an 8.5-minute mile pace for 20 minutes. For me (Ryan), it was difficult since I rarely run. Therefore, I was breathing heavy and sweating considerably at the end of the workout.
Surprisingly, the workout did not produce a very high average heart rate, 146 bpm. My lifting and cardio workouts regularly have me in the 150-170 bpm range.
Alex is a great runner, so this was easy for her but also produced a high average heart rate. She even burned more calories in the afterburn than she did in the burn. It was interesting to see how our bodies reacted differently to these workouts.
Running on the treadmill was boring for both of us. We much prefer to run outside. For me, it didn’t help that I was stuck watching a comedy cooking show in Japanese.
Day 2 – YouTube Cardio 1, Fitness Blender
YouTube Cardio 1, Fitness Blender
Today’s workout was a let down for both Alex and I. It was a HIIT workout, which is my favorite form of cardio, but the exercises were too short and separated by too many breaks. Therefore, our average heart rate was very low. For me, 130 bpm and for Alex, 115 bpm. This is much lower than yesterday’s treadmill workout.
This might be a great workout for the beginner, but for us, they were far too easy. It’s definitely not going to be the best cardio workout.
Alex also found the video to be misleading as it promised 188-375 calories burned (shown right on the screen). She topped off at 67 calories burned instead.
Day 3 – BOD Cardio 2, Insanity Max :30, Cardio Challenge
BOD Cardio 2, Insanity Max :30, Cardio Challenge
Day 3 was insane, hence the name Insanity. The Insanity Max:30 Cardio Challenge delivered a high average heart rate and calorie burn for both Alex and me.
It was a major challenge, and during the afterburn, I could tell my body was fighting to recover. I was amazed that I burned 653 calories from a 20-minute workout (including the 60-minute afterburn). Very impressive results for Alex, too, burning a total of 216 calories!
The workout consisted of 45-second moves and three short breaks. I credit these great numbers to the intensity, variety of muscle groups recruited, and the explosive total-body moves.
Day 4 – YouTube Cardio 2, POPSUGAR Fitness
YouTube Cardio 2, POPSUGAR Fitness
Today’s cardio workout was another free YouTube workout let-down, as you can see from Alex’s post in our Duo Life Community. It was just….
For us, slow also means boring, and that is never a good thing when it comes to workouts. They are hard enough to be consistent with when they are exciting, challenging, and bringing results.
This is another beginner’s workout, in our opinion. Maybe selecting free workouts based on the number of YouTube views was not the best choice.
I burned 68% fewer calories, and Alex burned 60% fewer calories than yesterday’s BOD Cardio 2, Insanity Max:30, workout. Wow, that would add up to a ton of calories after a few months of working out!
Day 5 – BOD Cardio 1, Transform :20 Sample Workout
BOD Cardio 1, Transform :20 Sample Workout
Today’s cardio workout was a burner! This was the first time ever doing this workout for both Alex and I. And, it took some focus to do the moves properly. Both of us hit our highest heart rate maximum yet! For me, 189 bpm, and for Alex, 170 bpm.
This routine requires a step, and that definitely increases the difficulty level and challenges the muscles in each leg (glutes especially) individually. Core exercises are a major component too. Since we were seated on the step doing core moves quite frequently, I was surprised that we maintained such a high average heart rate.
This cardio workout challenged not only our heart and lungs but also upper, lower, and core muscles. We both hit muscle failure in the 20 minutes so that is very impressive.
Day 6 – Exercise Bike
Today we followed the exercise bike program outlined in Appendix VI. As I reported to our Duo Life Community, this workout took me by surprise. I sweated like crazy, probably because my leg muscles were firing on the many steep hills built into the program.
Unfortunately, my heart rate dropped off quickly after the workout finished, and it ended up being the worst cardio workout for me. This surprised me as I thought it was far harder than the free Youtube workouts. However, this shows that muscle engagement during cardio workouts is critical. The exercise bike is not the best cardio work out.
Alex thought the exercise bike was pretty easy, which is interesting because, according to the heart rate analysis, it was a better cardio workout for her than the YouTube Cardio workouts. This just goes to show that everyone is unique! And it never hurts to have a heart rate monitor!
View All Heart Rate Analysis Graphs
Portion Control Container Tracking:
- Ryan: 7 green, 3 purple, 5 red, 4 yellow, 1 blue, 1 orange, and 6 tsp allowance
- Alex: 3 green, 2 purple, 4 red, 2 yellow, 1 blue, 1 orange, and 3 tsp allowance
We eat a mostly vegetarian diet (fully for Alex) of organic whole foods. We also stick to a 16/8 intermittent fasting plan.
For more details on healthy eating, see our Eat Clean Page.
- Select the Classic Cardio program (a random mixture of gradual and steep hills)
- Ryan: Difficulty level 13 of 25 for 20 minutes
- Alex: Difficulty level 9 of 25 for 20 minutes
- Maintained 70-100 rpms
- Never fell below 70 rpms (about 15 mph) on steep hills, and usually never fell below 75 rpms
So, what’s the best cardio workout?
Based on this data, total body HIIT. It should be fast-paced, incorporate bodyweight strength training, and keep you in zones 3, 4, and 5 for nearly the entire workout. It should be really hard, but you only have to do it for 20-30 minutes.
If you want effective cardio, there are a variety of great programs on Beachbody On Demand. Below is our review of Beachbody On Demand and once you sign up, these are the best (most effective) Beachbody workout programs.
If you have any questions about our experiment, ask away in the comments below.
For more helpful fitness resources, such as our 30-Day Ab Challenge, our guide on how to build a home gym, or the free 8-Week Resistance Band Workout Routine, head over to our Work Out At Home Page.
We also created the below free fitness plans and routines.
Our Fitness plans:
- 3-Month Marathon Training Plan
- 8-week total body Resistance Band Workout Routine
- 8-week, no equipment Bodyweight Workout Plan
- 6-week Couples Yoga Program
- 30-Day Ab Challenge
- 30-Day Plank Challenge
- Couples Workout Routine
- Bodyweight Workout for Beginners
- Couples Yoga Flow Routine
- Partner Core Exercise Routine
- Couples Pregnancy Workout Routine
- Our list of Free Beachbody Workouts
We hope that you get started and track your progress with our printable Body Measurement Chart.
8-Week Bodyweight Workout Plan
Download and instantly access the 8-week bodyweight exercise program including the following.
- Videos of the 70 best upper body, lower body, core, and total-body cardio exercises with professional instruction to ensure proper form.
- An 8-week workout calendar and rep tracker sheet with built-in variety and periodization.
- A program guide built for your current fitness level: beginner, intermediate, or advanced.
- Access to all future revisions to the program.
Plus, we're always here for support.
Hey we're Ryan and Alex
The creators of Ryan and Alex Duo Life. We are a husband-wife duo and “lifestyle engineers.”
After eight years working in the corporate world as engineers, we left our high-powered jobs to tackle our true passion — helping couples engineer their best lives.
The synergy of our engineering minds and ten years of health coaching experience produced Ryan and Alex Duo Life. Our mission is to help you transform your bodies, minds, and relationship as a couple.
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WoW and WoW! This makes an interesting read and surprising results. Body fat % difference between the two of you: who else on earth has 7%?
Fun to read you were watching a Japanese cooking show while on the treadmill! Very scientific approach and findings. Well explained. I now have to find a way to print this. Congratulations! Very impressed in Belgium.
Thanks for reading so thoroughly, Kathleen! We were also surprised by the results but the information helps up pick the best cardio workout that can bring results in 20 minutes. We have a lot to Duo, so we always try to keep our workouts less than 30 minutes long. If you right click anywhere on this page you should be able to send the article to a printer or print to PDF.
Hi guys! Just curious if you had replicates for your work out treatments? Confused by graphics with absolutely identical error bars…. Thanks!
Hey Brittney, great question. There are no replicates, and maybe we need to hire you to make our future graphs. You’re right, the error bars should not be on the graphs at all.
We would have loved to do replicates but the experiment already took a week to complete and it ran our schedule since we controlled food, water, workout time, sleep, no alcohol, etc.
We highly recommend you replicate the experiment yourself!