What symptom during an exercise test indicates the test should be stopped?

A drop in systolic blood pressure of 10 mmHg or below during an exercise test is a critical indicator that the test should be stopped. This drop can suggest a number of underlying issues, such as inadequate cardiac output or an abnormal response to physical exertion, which could pose significant risks to the individual. Monitoring blood pressure is an essential component of exercise testing, as it reflects how well the cardiovascular system is responding to the increased demands of exercise.

In a healthy response, systolic blood pressure typically increases during exercise due to increased heart output. A significant drop, however, can indicate that the cardiovascular system is unable to cope with the stress of exercise, potentially leading to adverse events such as syncope or cardiac complications. Therefore, this response requires immediate cessation of the test to ensure the safety of the participant.

Other symptoms like an increase in heart rate are expected as the body responds to exercise. Pain that is manageable does not necessarily indicate an immediate cause for concern unless it escalates to a higher level of discomfort or is indicative of a more serious condition. Stable blood pressure levels are generally a positive sign, suggesting that the individual's response to exercise is within normal limits and does not warrant stopping the test.