HMS, BM EQ-Bank 797 MC

During a progressively increasing exercise test, an athlete's blood lactate levels are measured at regular intervals. At which point would blood lactate levels begin to show a significant exponential increase?

When the anaerobic threshold is reached
When exercise intensity exceeds 85% of maximum heart rate
As soon as any exercise begins, regardless of intensity
When the aerobic threshold is reached

Show Answers Only

\(A\)

Show Worked Solution

Consider Option A:

Blood lactate levels remain relatively stable with small increases until the anaerobic threshold (lactate threshold) is reached.
At this point, lactate production exceeds the body’s ability to clear it, resulting in exponential accumulation in the bloodstream.

Other Options:

B is incorrect: 85% of maximum heart rate approximates the threshold for many, but heart rate doesn’t directly determine lactate accumulation; it varies by individual.
C is incorrect: Lactate is produced during all exercise, but at lower intensities, clearance mechanisms prevent significant accumulation.
D is incorrect: The aerobic threshold causes only a slight increase in lactate levels, not the exponential increase described.

\(\Rightarrow A\)