How to perform Orthostatic Test
Orthostatic heart rate reaction can be used to analyze an athlete's training state. When performing the Orthostatic test one should lie down for several minutes resting peacefully and fully relaxed and then stand up. The change from lying to standing position creates redistribution of blood volume. Systolic blood pressure decreases and heart rate increases. The peak heart rate is found approximately 15 seconds after standing up. With continued standing heart rate starts to oscillate at a certain level.
The test result i.e. the orthostatic heart rate is the difference between the heart rates at supine rest and at standing position. For example, if the average heart rate in a lying position is 56 and at standing 80, the orthostatic heart rate is 24 bpm. However, there are different opinions at what stage the standing heart rate should be taken. Some use the peak heart rate and others the average heart rate after the peak heart rate. Because precise instructions for performing the orthostatic test do not exist, the user should decide his/her practice and then perform the test always the same way.
The peak heart rate is usually interpreted to reflect parasympathetic nervous activity and heart rate at standing sympathetic activity, and they both are good indicators of disturbances in autonomic nervous system, for example overtraining.
Performing the Orthostatic test
1. Wear the transmitter and the wrist unit. Turn the wrist unit to a mode where you can see your heart rate.
2. Lie down and relax. It is recommended to relax at least 3 minutes.
3. Check your heart rate, and write it down.
4. Stand up and stay standing.
5. Check your heart rate, and write it down. You can use the peak heart rate i.e. the highest heart rate or the average heart rate after the peak. If you use the heart rate after the peak, stay standing at least 3 minutes. Note, that you should always use the same value, either the peak or the average.
6. Subtract the lying position heart rate from the standing position heart rate. The result is called the Orthostatic Heart Rate:
Orthostatic HR = ( HR at standing ) – ( HR at supine position )
Alternatively, you can record your test heart rate and transfer the data to the Polar PC software. Then check the heart rates from the Curve view. You can use, for example, the average heart rate at supine rest and the average heart rate during the standing position after the peak heart rate. The easiest way to check the values is to select the desired period; the average heart rate is displayed above the blue selection bar on the X-axis.
Perform the test at the same time of day to get comparable test results.
Analyzing the Orthostatic test
To follow and analyze your training state, enter your Orthostatic HR value to the Diary in the Polar PC software.
1. Open the Day Information page of the desired date.
2. Enter the value to the Orthostatic HR box.
You can view and analyze the values in reports:
1. Open a report.
2. Right-click on a report and select Report Properties.
3. Select a line graph in the Report Charts frame and click Edit.
4. In the Line Chart field, select Orthostatic HR.
You will get the best overview for the test values if you have the report summarized in days:
1. Open the Report Properties dialog and then the General page.
2. Select bar chart in the Report Charts frame (the topmost report type), and click Edit.
3. Select Days in the Bar Summarizing field.
Edit the line chart as desired in the Advanced page of the Edit Report Chart dialog. For example, you can set the color and the thickness of the line.
Interpretation of the results
- Previous Orthostatic test results are always the best reference for each person. A "database" of long time values is needed in order to be able to use the orthostatic test information to analyze the athlete's training state.
- Thus, at first a baseline measure over a longer time of easy training, for example two weeks, is needed. Compare future tests to this period to see possible changes. A distinct rise is a sign of insufficient recovery from the previous exercise.
- Usually at normal training state the orthostatic heart rate of an athlete is about 15-30 bpm. If the difference is more, the athlete is not recovered well enough and the danger of overtraining exists. However, heart rate reactions are very individual and individual baseline measurement is necessary.
- When you perform the orthostatic test over consecutive days you will learn the behavior of your body to different kinds of training. This will make the future training analysis with the overtraining test more accurate and detailed.
- Note that other sources of stress, beginning of a fever or an attack of the flu can result abnormal orthostatic response.
- The Orthostatic test is not a very accurate way to analyze an athlete's training state. The Polar OwnOptimizer test is designed for the same purpose and gives more accurate information. In addition to orthostatic test parameters e.g. peak heart rate at standing, Polar OwnOptimizer uses several other parameters measured and calculated from the test heart rate data.