We shouldn't exercise with a patient if their hemoglobin is under what value?

• A. 6 g/dL
• B. 7 g/dL
• C. 9 g/dL
• D. 8 g/dL

Answer: (D)

When the blood doesn’t carry enough oxygen, exercising increases the body's demand for oxygen beyond what the tissues can receive. Hemoglobin is the key oxygen carrier, so low levels mean the heart and muscles can become stressed, with a higher risk of fatigue, dizziness, tachycardia, chest pain, or fainting during activity. In rehabilitation practice, about 8 g/dL is the safety cutoff: below this level, exercise is generally postponed or significantly limited until hemoglobin rises or medical clearance is obtained. Values higher than 8 g/dL are more compatible with initiating or continuing light to moderate activity, with appropriate monitoring. So, the threshold to avoid exercise is 8 g/dL.