Final answer:
Unstable angina is an absolute contraindication for symptom-limited maximal exercise testing.
Step-by-step explanation:
The absolute contraindication for symptom-limited maximal exercise testing is unstable angina.
Unstable angina is a type of angina in which pain occurs during rest, lasts more than 15 minutes, and is of new onset. It is considered more dangerous and may be a sign of an imminent heart attack, requiring urgent medical attention.
Controlled hypertension, stable angina, and well-controlled asthma are not absolute contraindications for symptom-limited maximal exercise testing and can be considered for the test.