## Introduction: How to Calculate a Target Heart Rate Zone Using the Tanaka Method

Duration to complete instructions: approximately 5 minutes

__Materials: __

- stop watch or watch with second hand
- calculator
- pen and paper

In order to receive the best results while exercising you must know the intensity level (a percentage of your maximum heart rate in which the body is working at) of the cardiorespiratory exercise your body is actually working at. The maximum heart rate (MHR) is the highest number of beats your heart can beat in one minute. Your target heart rate zone is calculated for cardiorespiratory exercises - such as running, walking, biking or swimming - because it is measuring how hard your heart is working or how fast it is having to pump blood to your body.

To use your target heart rate zone while exercising, take your pulse in the same manner as described in step two. If your pulse falls between the numbers of your range, then you are successfully reaching your desired intensity level. If your pulse does not fall between the numbers of your range, then try to exercise harder.

To measure if you are reaching a certain intensity, you use the Tanaka method. The Tanaka method calculates a range for how fast your heart should be beating while exercising. The calculations will be explained in detail in the following steps.

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## Step 1: Find Your Maximum Heart Rate

The first step in calculating your target heart rate zone is to find your maximum heart rate. Again, your maximum heart rate (MHR) is the highest number of times in a minute your heart can beat. The numbers 208 and 0.7 are predetermined constants for the equation.

**MHR = 208 - 0.7 x your age**

Once your maximum heart rate is found, you round it to the nearest whole number. If the number has a decimal of 0.5 or greater, then round the number up. If the number has a decimal less than 0.5, round the number down.

*Note: For a sample calculation refer to the image above.

## Step 2: Finding Your Resting Heart Rate (RHR)

The second step is to find your resting heart rate also known as your pulse. Your resting heart rate is the number of times your heart beats in a minute while sedentary(at rest).

The pulse can be measured in two locations: the wrist or neck. To find your pulse in either locations use your index finger and middle finger. These two fingers are used because the pulse in the fingers is too weak to interfere with the pulse in your wrist or neck, and two fingers allow the pulse to be detected easier.

- To find the pulse in your wrist (as demonstrated in the image above):
- Hold one hand facing upwards in order for your wrist to be visible.
- Place the tips of your index finger and middle finger of the opposite hand on the same side of the wrist as the thumb.
- Move your finger tips to about a thumbs length away from the bend of your wrist until they fit into the groove of your wrist.
- You should be able to feel a beating sensation which is your pulse

- To find the pulse in your neck:
- Place your right index and middle finger to the left of your windpipe (the middle hard part of your neck)
- With your head looking straight forward, you should be able to press lightly below your neck to feel the pulse.

Once you locate your pulse, count the number of beats you feel for 15 seconds. Use a stopwatch or clock with a second hand in order to keep track of the time. This number is then multiplied by four in order to find how many times your heart beats per minute (bpm).

**RHR = number of beats during 15 seconds x 4**

## Step 3: Subtract RHR From MHR

Now that you have found your maximum heart rate and resting heart rate, you subtract RHR from MHR in order to find the number to multiply by the intensity in the next step. MHR was found in step one and RHR was found in step two.

**MHR - RHR**

*Note: For a sample calculation refer to the image above.

## Step 4: Determine the Intensity Range You Wish to Achieve

Current fitness level plays a role in determining the range of intensity desired for a work out. The chart above helps breakdown the different ranges of intensity based on how fit you are (fitness class) and how much cardio exercise you currently do (cardio activity level).

- Fitness class - how effectively the heart can pump blood through the body
- Cardio activity - any activity in which your heart is working harder - running, swimming, biking or walking

To better gauge what the different intensity levels mean here is a list of cardio activities and the associated intensity level.

- walking should be about 40% of your MHR
- jogging should be about 60% of your MHR
- sprinting should be about 85% of your MHR

## Step 5: Calculate Lower Intensity Heart Rate

Once you decide the intensity range you wish to work at, you can calculate the range for your heart beat.

To find the lower limit, you first begin by multiplying the smaller percent times the number found in step three (MHR - RHR). The result of this equation should be rounded to the nearest whole number before moving on to the next step.

**lower limit% x (MHR - RHR)**

Next you add your resting pulse back to this number to have your lower end target heart rate.

**[lower limit% x (MHR - RHR)] + RHR**

*Note: For a sample calculation refer to the image above.

## Step 6: Calculate Upper Intensity Heart Rate

The process to find the upper intensity of the range is the same as finding the lower limit except the upper limit is used instead of the lower limit.

To find the upper limit, you first begin by multiplying the smaller percent times the number found in step three (MHR - RHR).The result of this equation should be rounded to the nearest whole number before moving on to the next step.

**upper limit% x (MHR - RHR) **

Next you add your resting pulse back to this number to have your lower end target heart rate.

**[upper limit% x (MHR - RHR)] + RHR**

*Note: For a sample calculation refer to the image above.

## Step 7: Conclusion: Your Target Heart Rate Zone

You now have your target heart rate zone.

It is advised to recalculate your target heart rate every two months because as you exercise more your heart becomes more efficient. This means your heart will not have to work as hard (beat as fast) while doing the same activities.

With your target heart rate zone, you can ensure that you are working hard enough to strengthen your heart and reach your intensity goals.

## Discussions

3 years ago

Thanks for sharing :)