From the Guidelines
A Bruce test level of -0.4 peak indicates a low exercise capacity, which is a strong negative prognostic factor for cardiovascular health, as it suggests that you reached a point below the predicted exercise capacity before reaching your maximum heart rate or experiencing symptoms that required stopping the test. This result is concerning because low exercise capacity, generally defined as less than stage II of the Bruce protocol or ≤20% age- and sex-predicted values, is associated with a high risk for cardiovascular death 1, 2. The inability to perform an exercise test or reaching a low peak level, such as -0.4, is itself a strong negative prognostic factor.
Key Points to Consider
- The Bruce protocol is a standardized treadmill test where speed and incline increase every three minutes, and your performance is compared to population norms.
- A low exercise capacity, as indicated by a peak level of -0.4, suggests mild cardiovascular deconditioning but doesn't necessarily indicate heart disease.
- However, it is crucial to discuss these results with your healthcare provider, who can interpret them in the context of your overall health, symptoms, and other test results.
- To improve this result, consider gradually increasing your aerobic exercise under medical supervision, starting with 20-30 minutes of moderate activity like walking or cycling 3-5 times per week.
Prognostic Factors
- Other prognostic factors include failure to increase systolic blood pressure to >120 mm Hg or a sustained >10 mm Hg drop during exercise, ST-segment elevation, complex ventricular ectopy or arrhythmias during stress or recovery, and delayed heart rate recovery 1.
- The Duke treadmill score remains the most widely used method to assess risk and prognosis, which takes into account exercise time, ST-segment deviation, and the presence of angina 2.
Next Steps
- It is essential to follow up with your healthcare provider to discuss the implications of your Bruce test results and determine the best course of action for improving your cardiovascular health.
- Your healthcare provider may recommend additional testing or lifestyle modifications to reduce your risk of cardiovascular disease.
From the Research
Bruce Protocol Test Results
- A peak level of -0.4 in a Bruce protocol treadmill test is not a standard measurement or result that can be directly interpreted from the provided studies 3, 4, 5, 6, 7.
- The studies discuss various aspects of the Bruce protocol, including its use in assessing maximal fitness level 3, feasibility and safety in patients after acute myocardial infarction 4, and normative zones for ratings of perceived exertion (RPE) during graded exercise testing 5.
- Other studies examine the results of the Bruce treadmill test in specific populations, such as children after arterial switch operation for simple transposition of the great arteries 6, and the use of maximal exercise testing in a family physician's office 7.
- However, none of the studies provide information on a peak level of -0.4 as a result of a Bruce protocol test, suggesting that this may not be a valid or recognized measurement in the context of these studies 3, 4, 5, 6, 7.