How many times have you noticed people at the gym strapped to a heart rate device? Probably often enough to second guess your own routine, because that person must know what the heck they are doing! Maybe they don’t…….
Target Heart Rate and Training Zones
The philosophy on target heart rate zones are pimped out all over our gyms, with the recurring graphic on pretty much every treadmill that clearly illustrates how to identify the fat burning zone for cardio workouts. For instance the average gym goer believes that exercising at in the range of 60-70% of your max heart rate will allow you to burn the greatest “percentage” of calories from fat (relative to carbs, and protein). This is absolutely true, but incomplete.
Classic Equation to Figure Out Max Heart Rate
MHR = 220-Age
Looking at the chart above I would be burning the most fat (as a percentage) in the zone of 115-135 beats per minute. This roughly equates to a walk/jog on the treadmill for me. Hardly taxing, but a great example of how “percentage” can be a deceptive thing. While working at a lower intensity level we may be burning 50% of these calories from fat, and at higher intensity only 35% from fat, but at the higher intensity we increase the total volume of calories being burned.
I’m not trying to make you feel stupid, but the same logic when applied to the situation below helps us realize that percentage means nothing when we are after total volume instead! Do you want to burn a higher percentage of fat? Or do you want to burn more total fat? Buddy the “Cake Boss”wouldn’t fall for that logic!
I’m not a math teacher, but there is difference between percentage and total volume.
Let’s pretend we are cake bakers and make 10% profit on all the cakes we sell per week up to 100 units.
If we sell more than 100 units we only make 7% profit per cake.
If we measured our success strictly by percentage then it wouldn’t make sense for us to make more than 100 cakes, right?
And we could say our target profit zone is between 1-100 cakes because this is where we make the biggest percentage of profit.
Even though we only make 7% profit when we sell more than 100 cakes, there is a great incentive to sell more cakes (work harder).
The more cakes we sell (the harder we work) the greater total volume of profit we will make (fat we will burn)
Example Scenario Higher Percentage/Lower Volume (each cakes sells for $10)
Total Profit = units sold x (profit % x Unit Price)
Total Profit = 77 cakes x (10% of $10)
Total Profit = $77
Example Scenario 2 – Lower Percentage/Greater Volume
Total Profit = units sold x (profit % x Unit Price)
Total Profit = 1000 x (7% of $10)
Total Profit = $700
Moral Of The Story
Just like the cake baker should work harder to increase the total volume of sales and therefore profits, we to want to work harder and more intense to increase the total volume of fat we are able to burn.
CRANK THE VOLUME
Don’t be fooled by a percentage anymore!
What these charts fail to indicate however is the total volume of calories being burned in each zone. Obviously it is not just a simple explanation, nor is it an easy calculation as it does depend on the person. The point is, do you think that simply getting to the target heart rate zone and staying there (in the magical fat burning zone) is the most effective way to train to lose fat?
I have heard trainers tell people that training in the upper range of your target heart rate is dangerous and this is true (unless you are an elite level athlete and your sport depends on your ability to do this).
But new research has shown that exercising near your max rate for a short bout of exercise followed by active rest will actually help you burn more fat and get fit quicker. This is the philosophy behind High Intensity Interval Training.
Don’t Throw Out Your Heart Rate Monitors Yet!
High Intensity Interval Training is the new cardio. Everyone in the fitness industry is getting into this trend and I have every reason to support it.
Even though we poked fun at the target heart rate zone, there is some merit to it, and used strategically with HIIT can help produce excellent results. The target heart rate zone is great for people that are just getting back into shape, are nursing and injury or have just completed a HIITS session. If you have time I suggest you read this article at fitnessblackbook by Rusty Moore. He is a guru when it comes to lifting and using strategic cardio sessions to lose fat.
My suggestion is to implement HIITS and try to reach the higher limits of your maximum beats per minute.
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haha I’ve taught maths at Uni. and I stil get confused! … they say highest percentage of fat burning is Sleeping! yeah that’s my kind of workout!
For sure I prefer Hitt shorter amount of time and still creating a calorie deficit but you are right add in at the end some steady state cardio and that’s a powerful combination
raymond
Sleeping, go figure! Sleep is great for you, and the best part is that there is a good chance you will not consume any calories while sleeping! Unless you have an extreme sleep walking habit that takes you to the fridge every night.
- Jordan
Great way to put the “fat burning zone myth” to rest. This is another one of those things that just became fact over time. Sure, steady state cardio at a target heart rate may have it’s place in a routine, but HIIT at a higher heart rate is much more efficient for fat burning.
Dave,
Thanks man. I was just getting sick of hearing it, over and over!
Jordan
Another way that I like to put the target heart zone is watching a scary movie. While watching a scary movie, your heart rate increases and like you Jordan, I bet I’d be in my target heart rate zone/max fat rate zone of 125 or so. So that must mean I’m burning a ton of calories while just sitting there watching the movie, eating popcorn and drinking a beer, correct?:) And let’s not forget the other added benefit of interval training when it comes to calories burned: you’re going to burn a lot more calories after an interval session than you are with a slow steady state cardio session during the recovery process.
Mike,
Thanks for stopping by. I love the scary movie analogy. Like you mentioned, the after effects of interval training increase fat burning potential for sure.
Jordan
I have been testing the target heart rate on myself for several years now and found as you have pointed out, that high intensity intervals work best.
Anyone can try this on a treadmill, cardio equipment or even self monitored. When you perform at high intensity your heart rate will shoot up to higher levels (the danger zone in the chart above), but when you decrease the intensity for a couple of minutes the heart rate drops back down to cardio conditioning.
Do this several times over a period of 15 to 20 minutes and your cardio levels will have been performing more effectively than if you had done a long, steady state fat burning session.
-Sam
Sam,
Thanks for leaving a comment. I did not mean to bash the heart rate devices (I too wore one for a while). I just think it is necessary for people to realize that just because they are burning a higher percentage of calories from fat using low level cardio doesn’t mean they are burning more in total.
I also don’t think people should miss out on the benefit of reaching and exercising in the so called “danger zone” as you mentioned.
Jordan
Jordan,
Great mathematical example! I’m a sucker for numbers so I really got a kick out of this. Another crazy myth that always makes me laugh is that you should eat more food so you can burn calories from digesting that food. The calories you burn digesting the food doesn’t make up for the calories you take in from eating, so it won’t make you lose weight. Sometimes a simple math lesson is quite an eye-opener (or just a reinforcement of common sense).
Alykhan