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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 6 of 6 · Your appointment

← 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 6

Preparing for your appointment

  • Compare what you can do now with what you could do before.
  • Record when fatigue began and whether it is worsening.
  • Note sleep quality, snoring, or breathing pauses noticed by someone else.
  • List breathlessness, chest discomfort, palpitations, swelling, or bleeding.
  • Bring medicines and doses, including supplements and recent changes.

Ask which causes are being considered, what activity is safe, and when to reassess. Bring previous heart tests and relevant laboratory results if available.

A specific example—“I now need to stop halfway up the stairs”—can help your clinician understand the change.

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.