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PATIENT EDUCATION · FATIGUE & REDUCED EXERCISE TOLERANCE

Fatigue and reduced exercise tolerance

Understand low energy and reduced exercise tolerance, possible causes, warning signs, testing, and treatment.

Section 3 of 6 · When to seek help

← Fatigue and reduced exercise tolerance: the short explanation
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All 6 sections, including text and pictures · 22 pages

What should I do now?

Call 911

Call 911 for new or unexplained chest pressure that persists or returns, severe trouble breathing, collapse without normal recovery, or sudden face/arm weakness or trouble speaking. Do not drive yourself.

Contact your care team

Contact your care team for persistent or worsening fatigue or a meaningful decline in your usual activity.

Keep your care plan

Record how symptoms affect daily tasks, and review sleep and medications with your clinician.

SECTION 3

When should I seek help?

Call 911 for sudden severe weakness or fatigue with chest discomfort, severe breathlessness, fainting, or stroke symptoms.

Heavy bleeding, vomiting blood, or black stools with weakness or dizziness also require urgent medical attention.

Arrange a visit for a persistent change

Contact your clinician if fatigue limits normal activities, is getting worse, or continues despite reasonable rest. Mention unexplained weight loss, fever, swelling, or a major change in walking ability.

Sudden exercise intolerance should not be pushed through. Stop the activity and seek care appropriate to the accompanying symptoms.

Sources & further readingMedlinePlus: FatigueMayo Clinic: Causes of fatigueAmerican Heart Association: Heart failure symptomsAmerican Heart Association: Valve disease symptoms

Updated October 2026. Educational information; your own care plan may differ. Medical illustrations are simplified examples for teaching.