Being overweight is a problem. Can cardio help solve this?
There is a question that seems to invariable always present itself to us when we embark on a weight loss venture…
Will cardio help me lose weight?
We know that exercise in general is healthy and beneficial to the human body in many ways, and some people do things regularly that fall into this category. Playing sports of almost any kind typically constitute themselves as effective exercise, and almost always have cardio centric elements to them.
However, if you are someone who doesn’t have a habit in your life established, the question of what to do can be a daunting one. Especially if you are in the all too common scenario of many individuals in this country who participate in a primarily sedentary lifestyle and have suffered the effects of this on their physical state.
Being out of shape and overweight with a lifestyle that includes little to no exercise is becoming the norm statistically.
A whopping 68.8 percent (more than two thirds) of adults, and about one third of children and adolescents are considered to be overweight or obese.1
I like to think that most people are not pleased with this, and want to do something about it.
So back to the cardio question…
Yes, cardio can help, but let me elaborate…
When we use the term cardio, we are referring to cardiovascular exercise, which is any exercise that raises the heart rate.
The heart, lungs and other organs involved in the cardiovascular system are muscles, and increased movement and work makes them stronger and better at performing their job, just like any other muscle.
As you can imagine there are many different ways to increase your heart rate with exercise, but which one is best solution for the problem at hand?
If a reduction in body stores of any kind are desired, maintaining a calorie deficit is key, because no amount of exercise makes anyone exempt from the laws of energy balance.
But exercise activity does play a role in this equation, due to the fact that cardio is one effective way to increase energy expenditure. In this sense, the answer is that cardio is not required for weight loss, but it can absolutely be used for this purpose.
The Best Cardio for Fat Loss.
When we set out to do something about the extra pounds that are bogging our life down, we tend to want the fasted most effective way possible.
It goes without say that while we do want to see the scale going down, what we are really after is fat loss, not just weight loss in general, and if you’ve chosen to employ cardio to help you on this front there are some diverse ways to go about it that can make an enormous impact on results.
As far as the type of activity goes, this is not of as much importance as you would think. After all, running, biking, and swimming all raise your heart rate. Choose an activity that you enjoy, because it’s most important that you adhere to it and can maintain it long term.
Beyond adherence, the protocol you choose to apply to your cardio activity is of much importance in terms of results.
There are two protocols that can be applied to almost any cardio activity.
- Steady State Exercise (SSE)
- High-Intensity Interval Training (HIIT).
The primary difference between these protocols is intensity.
Perceived intensity can vary with each person (how hard the exercise feels) and while you should be conscious of this, it’s not how you measure the level of intensity.
Intensity refers to how much energy is being expended. General terms classify intensity as low, moderate, or high.
The higher the intensity, the bigger the impact on physiological variables like hearth rate and breathing.
As you can imagine, there is a limit of how long a given intensity can be maintained. This limit approaches faster the higher the intensity.
If we wanted the best return on our investment in terms of time spent engaging in cardio, we would simply use the logic that maintaining the highest intensity (thus expending the most energy) would be the obvious choice.
20 minutes of constant high intensity exercise would clearly use more energy than 20 minutes of constant low intensity exercise…
But of course, our bodies can’t maintain the highest level of intensity for long, so this complicates the solution that comes from this logic.
This is where HIIT comes in.
Steady State exercise (low intensity) can be maintained for extended periods, and can add up over time. So, it’s not useless, but HIIT can deliver on the efficiency front were as SSE cannot.
This is because the HIIT protocol consists of intervals that alternate between high intensity (work) and low intensity (recovery), and this is a sustainable approach to expending the most energy in a given period of time.
This work/recovery ratio can vary. Some of the different kinds of HIIT protocol call for longer or shorter intervals, and the length of the intervals can often be suited for one’s level of conditioning and ability.
Regardless of the interval length, the evidence that HIIT is superior to SSE is very clear in scientific research, and there are some insights as to how HIIT yields better results in fat loss specifically.
Researchers at Laval University conducted a study that compared the effect of these two different modes of training on body fatness.2 The lower intensity group’s training period was 20 weeks, and the high intensity group’s training period was only 15 weeks. Despite the estimated total energy cost of the HIIT group’s training being less than half that of the lower intensity group, the HIIT group lost more subcutaneous fat in the skinfold tests, and it wasn’t by a small amount either. The HIIT group’s decrease in skinfold measurements was nine times greater than that of the lower intensity group… and again, their training period was 5 weeks shorter!
In another study by the University of New South Wales involving 45 young women, researchers concluded that HIIT three times a week for 15 weeks compared to the same frequency of SSE was associated with significantly larger reductions in total body fat, subcutaneous leg and trunk fat, and insulin resistance.3
When you get down to an outright comparison of HIIT and SSE, there is one study that involved both men and women performing 4-6 intervals lasting 30 seconds against an hour of SSE cardio.8. Again, the HIIT group burned more energy in their workouts and lost more fat than the SEE group regardless of the fact their sessions were much, much shorter. The results here exemplify just how much more efficient HIIT is for energy expenditure.
The consensus is clear that if losing more fat in a shorter period of time is of interest to you, HIIT is the way to go.
The Best Type of HIIT Protocol.
The difference from one HIIT protocol to the other is expressed in how long the work/recovery intervals last.
In the studies I have seen, the ratio used varied anywhere from 1:1 to 1:8, and the difference was primarily in how long the work interval was. The longer the work interval, the more recovery was necessary before it could be performed again. The total amount of exercise also varied from 5-10 minutes to even 20 or 30 minutes. Neither of which are very long duration compared to your typical SSE cardio recommendations of an hour or more.
For example, a short interval ratio would be 6 seconds work to 12 seconds recovery (1:2). For 15 minutes of cardio, this would be 50 intervals.
A longer interval ratio may be 30 seconds to 120 seconds (1:4 ratio), which results in fewer intervals, but each work interval would be longer and more difficult.
The more time spent in the high intensity interval, the more effective the cardio will be in increasing energy expenditure and reduction of fat.
I recommend a ratio of 1:2 working towards a 1:1 for most individuals, or if you are not conditioned enough for this, start at a ratio of 1:4 and work towards shrinking it slowly week over week. I like starting with a 30 second work interval because I’ve found it to be sufficient in achieving the required level of intensity.
How to Measure Cardiovascular Intensity
There are two ways to determine the level of intensity that you reach with exercise.
- Heart Rate
- VO2 max
Heart rate is a measurement of exercise activity6 and can be an indicator of how challenging the activity is for your body to perform. This is useful because it is not difficult to find a method for tracking your heart rate in beats per minute (BPM)
You can simply use your wristwatch or there are many electronic devices that sport heart rate monitors, most stationary cardio machines and many of today’s smart devices come equipped with one.
From here you must determine the BPM range you need to be in to be considered high intensity.
The age-old formula for determining maximum heart rate is 220 minus your age, and this is fairly accurate for most anyone who is not of either very old age or compromised physical condition (elderly, those in extreme ill health).
High intensity as measured by percentage of maximum heart rate is considered to be somewhere between 70-90%, and where you fall in this range will be determined by your level of athletic conditioning. So, don’t stress it if you aren’t hitting the top end of this range when you are first starting out.
The second measure is more related to your breathing during exercise.
VO2 max goes by many names (maximal oxygen consumption, maximal oxygen uptake, peak oxygen uptake or maximal aerobic capacity).
The designation is derived from V-volume, O2-oxygen, M-maximum, and refers to the maximum rate of oxygen consumption during exercise.
The actual VO2 max is reached when oxygen consumption stays the same despite increases in workload.
Measurement of VO2 max requires specialized equipment, and I don’t expect anyone to have their VO2 max measured just for the general purpose of a cardio workout.
I do however outline the basics of VO2 max so that you may understand what it is, and what indicators will represent a high percentage of VO2 max having been achieved.
If you have ever sprinted, all-out, for about as long as you can, until your heart is racing and your breathing about as labored as you can imagine, this was most likely your VO2 max or very close to it.
Now I’m not proposing this procedure, but anyone who has gotten out of breath from a bout of exertion knows the labored breathing I mentioned just now.
I have found that an excellent way to tell if you are approaching your VO2 max is to pay attention to breathing. If your breathing rate doesn’t increase at a given pace or resistance, you are not near the range required to be considered high intensity. When your rate of breathing is noticeably increased, you’ve reached the low-moderate intensity range. And when your rate of breathing is to the point where it would be difficult to speak whole sentences or carry on a conversation, you’ve reached the high intensity range.
Follow this simple approach of giving attention to both heart rate and breathing and you will have no trouble ensuring that you reach the level of high intensity with your cardio activity of choice.
The Best HIIT Workout
Now that you know what HIIT is and how to measure your level of intensity, the next step is to choose your exercise activity and build a high-intensity interval workout routine.
As I’ve stated this can be applied to many types of activity. Common examples include both stationary or mobile forms of running, biking or rowing.
I personally happen to really enjoy cycling outdoors, and have built a very effective HIIT routine for it that serves me well in my fat loss endeavors, all while doing something I actually like.
Any able-bodied dieter or gym goer can handle a few HIIT sessions a week lasting 20-30 minutes in duration (60-90 minutes total weekly volume), and this will have a marked impact on total energy expenditure for the week.
I have seen more weekly volume assigned to subjects in some research to the tune of 6 sessions per week alongside resistance training, and the results were pretty staggering.7
However, I would not recommend this much volume, simply because this would be beyond difficult to adhere to, and I guarantee you the people involved in this study did not have a fun time.
A 30-minute routine using the optimal ratio would look like this:
(expressed in 0:00 minutes/seconds format)
- Warmup period – 3:00
- Work interval – 0:30
- Recovery interval – 1:00
- Rounds – 16
- Cooldown period – 3:00
This routine spread across three days a week like Monday-Wednesday-Friday or Tuesday-Thursday-Saturday works wonders and will put you at the top end of the weekly volume range.
If you feel like the above routine is too much for you to start with, either drop it to only two sessions a week or alter it as follows:
- Warmup period – 3:00
- Work interval – 0:30
- Recovery interval – 2:00
- Rounds – 10
- Cooldown period – 2:00
This will give you the same 30 minutes per session as before, and you can work towards changing the ratio as your conditioning and ability improves.
You will find that as your body adapts to these workouts the work intervals will get easier, and you will likely need to increase the length of them to keep the same level of effectiveness, or essentially make them harder again.
This can be done by adding time to the work interval and removing time from the recovery interval. This will, over time shrink your ratio closer to 1:1 which can be very intense, but results in a killer HIIT workout that will burn a lot of calories, making it even more effective for increasing energy expenditure.
Another tip is to use an app for the routine rather than go through the trouble of timing it with a stopwatch, here are two that I’ve found to be simple and easy to use:
From here the task is simple. Apply this to your choice of cardio activity and that’s it!
Sum and Substance
When we look at what cardio brings to the table in terms of potential value in solving the prominent issue of overweight and obese individuals, it’s clear that it can be a powerful tool when combined with calorie restriction.
Even though you can absolutely lose fat without the use of cardio, HIIT in particular has some hearty advantages in this effort and can be especially useful when performed correctly.
- If you wish to employ cardio for fat loss, the evidence is clear that high-intensity interval training (HIIT) is the superior choice over steady-state exercise (SSE).
- HIIT cardio is very advantageous in terms of time efficiency and return on investment when compared to SSE.
- Protocols for HIIT cardio can vary and will accommodate various levels of ability. The optimal ratios being 1:2 or 1:1 depending on your conditioning over time.
- Measuring training intensity is no challenging task when attention is given to heart rate and breathing.
- The best HIIT workout can easily be done 2-3 days per week in relatively short sessions no longer than 30 minutes
- There are simple tools that help you deploy and track HIIT workouts, so anyone can do it!
I’m here to tell you that If you have an activity you enjoy, and want to use it as a way to help you in your fat loss efforts, HIIT cardio can organize that activity into a powerful workout that you actually enjoy.
So why not jump on the HIIT bandwagon?
Thanks for reading!
If you like my take on this, have questions or something to add to it, comment below or feel free to reach out to me via email or social media.
I’ll always do my best to help 🙂
- Overweight and obesity statistics in America. https://www.niddk.nih.gov/health-information/health-statistics/Pages/overweight-obesity-statistics.aspx
- Impact of exercise intensity on body fatness and skeletal muscle metabolism. Tremblay A, Simoneau J-A, Bouchard C.Metabolism. 1994;43(7):814–818 https://www.ncbi.nlm.nih.gov/pubmed/8028502
- The effects of high-intensity intermittent exercise training on fat loss and fasting insulin levels of young women. Trapp EG, Chisholm DJ, Freund J, Boutcher SH..International Journal of Obesity. 2008;32(4):684–691. https://www.ncbi.nlm.nih.gov/pubmed/18197184
- Absence of exercise-induced variations in adiponectin levels despite decreased abdominal adiposity and improved insulin sensitivity in type 2 diabetic men. Boudou P, Sobngwi E, Mauvais-Jarvis F, Vexiau P, Gautier J-F. European Journal of Endocrinology. 2003;149(5):421–424. https://www.ncbi.nlm.nih.gov/pubmed/14585088
- Mourier A, Gautier J-F, De Kerviler E, et al. Mobilization of visceral adipose tissue related to the improvement in insulin sensitivity in response to physical training in NIDDM: effects of branched-chain amino acid supplements.Diabetes Care. 1997;20(3):385–391. https://www.ncbi.nlm.nih.gov/pubmed/9051392
- VO2max: what do we know, and what do we still need to know Levine, B.D. Institute for Exercise and Environmental Medicine, Presbyterian Hospital of Dallas, TX 75231. The Journal of Physiology, 2008 Jan 1;586(1):25-34. Epub 2007 Nov 15.
- Thomas M Longland, S.C.M.A. (2016). Higher compared with lower dietary protein during an energy deficit combined with intense exercise promotes greater lean mass gain and fat mass loss: a randomized trial. 103(3), 738 http://ajcn.nutrition.org/content/early/2016/01/26/ajcn.115.119339.abstract
- Run sprint interval training improves aerobic performance but not maximal cardiac output. Macpherson RE1,Hazell TJ, Olver TD, Paterson DH, Lemon PW. https://www.ncbi.nlm.nih.gov/pubmed/20473222