The threshold below which exercise is generally not advised due to WBC count is what?

• A. 5,000
• B. 2,000
• C. 8,000
• D. 12,000

Answer: (A)

White blood cell count helps determine whether it's safe to exercise. Normal WBC counts are roughly 4,500–11,000 per microliter, and when the count falls below a safety threshold, the risk of infection during exertion increases. Clinically, about 5,000 per microliter is used as the threshold below which exercise is generally not advised, because immune defenses are waning and even light activity can raise infection risk. Counts around 8,000 or 12,000 are well within the normal range and do not require withholding exercise for this reason. A count as low as 2,000 would be a much more severe level of leukopenia and represents a clear contraindication, but the standard cutoff used to guide these decisions is 5,000.