The age old idea of low impact cardiovascular exercises to burn fat is no longer holding up to new research and fitness testing. While low impact cardio is still good for you and will help in weight loss, it is no longer deemed to be the best and fastest method. So what is? What should you be doing to target fat burn, and how often should you be doing it? Let’s take a look at cardio intensity and how much you should do.
First, let’s look at some math. The chart1 below shows your Heart Rate (HR) percentage of your maximum HR (HR max), and how much fat you will burn. A quick and easy way to calculate your HR max is to subtract your age from 220. For some other methods to calculate your HR max, check out this website http://www.brianmac.co.uk/maxhr.htm. The best way to determine your HR max is to work with a trainer and do physical testing.
HR % from max
|
% fat burned from total calories burned
|
65 -70 %
|
60 %
|
70 - 75 %
|
50 %
|
75 - 80 %
|
35 %
|
80 - 85 %
|
20 %
|
85 - 90 %
|
10 %
|
90 - 95 %
|
5 %
|
95 - 100 %
|
0 %
|
The chart above just shows the percent of calories that is burned from fat, the remaining calories are mostly burned from carbohydrates. Note, it is not recommended to workout at 100% of your maximum heart rate.
Looking at the chart, it appears that the low impact HR zone burns the most fat, and thus should be the best one to do. What it isn’t showing you, is the increase in calorie burn. As you increase your HR, you will burn more calories in a shorter period of time. There is of course a limit. If you are training above 85% of you HR max, then you significantly decrease your fat burn percent. This is due to the high intensity of the training, which becomes anaerobic instead of aerobic. These intensities are also very difficult to sustain, so the amount of calories burned will be lower. This range of exercise should be done during athletic training, and not for fat burning. Summarizing the chart above, it appears that a mid-range of intensity is the best for burning fat quickly.
Looking at the chart, it appears that the low impact HR zone burns the most fat, and thus should be the best one to do. What it isn’t showing you, is the increase in calorie burn. As you increase your HR, you will burn more calories in a shorter period of time. There is of course a limit. If you are training above 85% of you HR max, then you significantly decrease your fat burn percent. This is due to the high intensity of the training, which becomes anaerobic instead of aerobic. These intensities are also very difficult to sustain, so the amount of calories burned will be lower. This range of exercise should be done during athletic training, and not for fat burning. Summarizing the chart above, it appears that a mid-range of intensity is the best for burning fat quickly.
What exactly should you be doing in the mid range? How much should you do? The goal you should be aiming for is about 70% of your HR max. Make sure this is a sustainable range for you, you want to maintain this HR during your entire exercise. If you are struggling reaching 70%, then lower your goal to 60%, and keep going until you get to a rate that you can sustain. If you are just starting to workout, you may find that you need to start at a lower HR in order to complete the workout.
Now, how often should you do cardio? Start with 3 days a week for 20 minutes. As that gets comfortable, gradually increase by 5 or 10 minutes until you can do 45 minutes. Once you can do that, increase your intensity, you may also need to decrease the total time. Work your way back up to 45 minutes! Keep repeating this until you reach 85% of your HR max. Once this is comfortable, it is time to move on to other exercises, which will not be covered in this post.
I want to quickly go over some of the benefits of the lower range of cardio workouts, 50 - 70 % HR max. Below are a few reasons that you will want to start in this range, or even stick to this range of intensity.
Now, how often should you do cardio? Start with 3 days a week for 20 minutes. As that gets comfortable, gradually increase by 5 or 10 minutes until you can do 45 minutes. Once you can do that, increase your intensity, you may also need to decrease the total time. Work your way back up to 45 minutes! Keep repeating this until you reach 85% of your HR max. Once this is comfortable, it is time to move on to other exercises, which will not be covered in this post.
I want to quickly go over some of the benefits of the lower range of cardio workouts, 50 - 70 % HR max. Below are a few reasons that you will want to start in this range, or even stick to this range of intensity.
- You are new to cardio exercises
- You have breathing problems
- You have joint issues, this range will have low impact activities, although there are some activities you can do to increase your HR that will not impact your joints
- You have a lot of time to exercise
- It includes activities you enjoy
In summary, using any cardiovascular exercises to burn fat and lose weight will be beneficial. In order to get the most benefit from your cardio exercise, increase your intensity but keep it at a sustainable rate. Cardiovascular exercise to lose weight should also be combined with weight training and a well balanced diet in order to maximize results. The best way to get started is to find something you enjoy and stick to it!
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