The Importance of Your Target Heart Rate for Weight Loss Success

Your cardio exercises should be done for a minimum of 20 minutes with a target heart rate in what I call the “weight loss zone.” The weight loss zone is considered 70-80% of your maximum heart rate. Your maximum heart rate can be accurately measured by taking a treadmill stress test. However, unless you’re a professional athlete or you absolutely want to know your exact maximum heart rate, taking such a test isn’t necessary. To get an approximate measurement, which is all you need for effective weight loss, take 220 minus your age. Here is how you calculate the target heart rate in the weight loss zone for a 35 year old:

Calculating Maximum Heart Rate
220 – 35 = 185

Calculating the Target Heart Rate for the Weight Loss Zone
70% of maximum heart rate: 185 x 70% = 129.5 (round up to 130)
80% of maximum heart rate: 185 x 80% = 148
The "Weight Loss Zone" is 130 - 148

In this example, a 35 year old should exercise a minimum of 20 minutes with a target heart rate of 130 – 148 for maximum weight loss results.

The reason your target heart rate is so important is that it reflects the rate at which your body is using oxygen, as well as the rate at which it is burning calories (metabolism). The more oxygen you’re using, the more calories you are burning. If you exercise in the weight loss zone, you’ll be using the required amount of oxygen that is necessary to burn excess calories.

Once you reach your ideal weight, you can exercise in the “maintenance zone.” The maintenance zone is a target heart rate of 60-70% of your maximum heart rate. You don’t want to exercise with a target heart rate lower than 60% of your maximum heart rate because it will be a waste of your time. You will not see any results exercising at that level.

When you first start exercising, you may not be able to exercise in the “weight loss zone” for a minimum of 20 minutes. When I first started exercising, it was very difficult for me because I was so out of shape. The good news is, if you stick with it and push yourself, it gets easier and easier everyday. I now exercise regularly at 80% of my maximum heart rate with relative “ease.” If someone would have told me when I started that I would be able to exercise at this level, I would have thought they were crazy! The key is to start out slow. Aim for 10 minutes in the “weight loss zone” initially and then gradually work your way up to 20 minutes. An easy way to accomplish this is to add 1-2 minutes to your workout every week. Before you know it you’ll be up to 20 minutes or more!

How to Determine if You Are Exercising in the Weight Loss Zone
There are three primary methods to determine if you are exercising in the weight loss zone. They are, from best to worst: heart rate monitors, your breathing rate and checking your pulse.

Heart Rate Monitors
The most accurate and effective way to determine if your target heart rate is in the weight loss zone is to use a heart rate monitor. A heart rate monitor consists of two pieces – the monitor that straps around your chest and a wrist watch receiver. When you turn it on, the monitor detects your heart rate and sends the information to the receiver. The wrist watch displays your current heart rate. All you have to do during your exercise is simply look at your wrist watch and you’ll have an instant reading of your heart rate.

Not only are they incredibly easy to use, but they’re fun to use as well. It’s interesting to watch how your heart rate responds to different exercises. I highly recommend a heart rate monitor as one of your first purchases towards achieving your weight loss goals. Heart rate monitors are inexpensive, easy to use and last a long time (I’ve had mine now for five years).

Breathing Rate
Your breathing is a great indicator of how hard you are working. By determining how hard you are breathing, you can get a general idea of what level of intensity you are working. Most health clubs post exertion charts near their aerobic exercise equipment to give their members an idea of what level of intensity they are exercising. These charts vary from club to club but they give the same basic information. They attempt to give you an idea of what your breathing should feel like at various levels of intensity. Pay attention to these charts as they can be helpful guides.

If you don’t have these charts to refer to, here is a general guideline of what your breathing would feel like if your target heart rate is in the weight loss zone. Your breathing would be deep and you would definitely be aware of it. You could carry on a conversation, but you would probably prefer not to. It is the feeling you’d have exercising vigorously. If you were exercising in the higher end of the weight loss zone (a target heart rate at 80% of your maximum heart rate), you would have a strong feeling of fatigue but you would feel you could still maintain that intensity for the rest of your exercise. Your breathing would be deep and you could still carry on a conversation but you wouldn’t feel like it. Exercising at this level is difficult for many people.

Checking Your Pulse
The third and least recommended method in determining if your target heart rate is in the weight loss zone is by manually checking your pulse. You have to periodically pause during your exercise and check your pulse to calculate your heart rate. There are two red flags about this method that make it hard to recommend. First, for aerobic exercise to be effective, it requires constant and vigorous activity without interruption. This method requires you to pause periodically, or at the very least significantly slow down your exercise to take your pulse. Second, for many people (I’m one of them) it can be difficult to find your pulse – causing an even longer interruption in your exercise. It is for these reasons that most health clubs today highly recommend the use of heart rate monitors or exertion charts as a guide.

Final notes on your target heart rate…
Each person’s weight loss zone is unique. For example, you may have to exercise more or less than the next person to reach and maintain a target heart rate of 70-80% of your maximum heart rate. If you exercise with a partner, be sure you exercise independently to maintain your own weight loss zone. When I exercise with my wife, her weight loss zone is much different than mine. We can be jogging together and while her target heart rate may be at 70% of her maximum heart rate, mine may be closer to 60% of my maximum heart rate. In order for me to reach my weight loss zone, I need to crank it up a few notches and do a harder jog than her. What I usually do is continue to jog at my wife's pace (because I'm such a sweet guy) but after she's done I'll continue to jog at a harder pace for an additional 20-30 minutes so that I can get my "full" exercise in.

Finally, there are times when you will want to change your intensity level. For example, if you’ve been exercising at 70% of your maximum heart rate and you reach a weight plateau, you may want to strive to exercise at 80% of your maximum heart rate for a few days a week. You may also want to interval train, which is when you exercise at different levels during your exercise – you exercise for a few minutes at 70% of your maximum heart rate and then you ramp it up to 80% of your maximum heart rate for a few minutes and then back to 70% and so on.