Treadmill protocols are sets of established criteria used for conducting a cardiac stress test on a treadmill. During a stress test, you run on a treadmill for a prescribed period of time. Technicians measure how hard your heart is working under increasing speeds and inclines of the treadmill. The results can give you and your doctor a good idea of your overall health profile, so you know how far you can safely exert yourself during exercise.
Four Main Protocols
There are four primary methods — or protocols — developed specifically for conducting a cardiac stress test. They are the Bruce Protocol, the Modified Bruce protocol, the Naughton Protocol and the Modified Naughton Protocol. Each protocol targets a different patient population: those who are fit, who may have cardiac problems, who have suffered from a cardiac event or who are elderly or unhealthy. The variables in the test are the speed of the treadmill, the incline settings and how they are adjusted throughout the test and rest periods during the test.
The Bruce Protocol
The Bruce Protocol is the most common for conducting a stress test. It's used to determine your cardio fitness. During this test, sticky electrocardiograph leads wired to an ECG machine are attached to the chest and your heart rate is graphed during exercise in seven increasingly difficult three-minute stages of effort on a treadmill. The treadmill starts at 1.7 miles per hour at a 10-percent incline. The incline is increased by 2 percent every three minutes, while the speed is increased in stages until the maximum speed, 7.5 miles per hour, is achieved at a 28-percent incline.
Modified Bruce Protocol
The Modified Bruce Protocol is an easier version of the Bruce Protocol. Your doctor might recommend it if you are in poor health or have a history of cardiac troubles. During this test, you wear electrocardiograph wires while walking on a treadmill that starts out at out at 1.7 mph — the same standards of the Bruce Protocol. The difference between the two is that the incline during the test is increased at about half the rate as in the Bruce Protocol, making it a less stressful stress test.
Naughton and Modified Naughton Protocols
The Naughton and Modified Naughton Protocols are the least stressful of the three most popular methods for conducting a cardiac stress test. They are designed for high-risk patients who might not be able to withstand the rigor of either Bruce protocol. In the Naughton Protocol, there are 10 stages of exercise of three minutes each. Each segment is followed by a three-minute rest period. In the Modified Naughton, the treadmill speed is set through the test at 2 mph. The stress comes from an incline that increases 3.5 percent every two minutes during the test until it gets to 21 percent, or until the you cry "Uncle!"
- American Heart Association: Exercise Stress Test
- Top End Sports.com: Bruce Protocol Stress Test
- Cardiophiloe.com: Modified Bruce Protocol; Johnson Francis
- Exercise Testing for Primary Care and Sports Medicine Physicians: Corey H. Evans Russell D. White; 2009
- Jupiterimages/Photos.com/Getty Images
This article reflects the views of the writer and does not necessarily reflect the views of Jillian Michaels or JillianMichaels.com.