ACSM Personal Trainer Certification Practice Exam

What effect does aerobic exercise have on blood lactate levels during rest?

1. It increases blood lactate levels

2. It decreases blood lactate levels

3. It has no effect on blood lactate levels

4. It causes variable blood lactate levels

The correct answer is: It decreases blood lactate levels

Aerobic exercise typically leads to a decrease in blood lactate levels during rest due to the body’s enhanced ability to utilize oxygen for energy production. When an individual engages in regular aerobic exercise, several physiological adaptations occur, such as increased mitochondrial density and improved efficiency of the cardiovascular and respiratory systems. These adaptations allow for optimal use of oxygen, leading the body to primarily rely on aerobic metabolism, which generates energy with minimal lactate production. At rest, trained individuals usually have a better capacity to clear lactate from the bloodstream as well, since their bodies are more efficient at transporting and using lactate as a fuel source. Consequently, this proficiency in lactate clearance and use contributes to maintaining lower blood lactate levels during periods of rest after engaging in aerobic activities. As a result, the effects of aerobic exercise are generally characterized by a decrease in blood lactate levels during rest due to these physiological adaptations and improved metabolic pathways.