Certified Personal Trainer (NSCA) Practice Exam

What is a benefit of performing warm-up activities?

1. A. Muscle blood flow increases

2. B. Muscle viscosity increases

3. C. Nerve impulse velocity decreases

4. D. Nerve receptor sensitivity decreases

The correct answer is: A. Muscle blood flow increases

Performing warm-up activities has several important benefits, and one of the key advantages is that muscle blood flow increases. During a warm-up, the body's temperature rises, which promotes vasodilation—the widening of blood vessels. This process enhances circulation, allowing more oxygen and nutrients to reach the muscles, which prepares them for more intense physical activity. Increased blood flow also helps to remove metabolic waste from the muscles, reducing the likelihood of injury and improving overall performance. In contrast, the other options do not reflect the benefits of a warm-up. For instance, muscle viscosity actually decreases with an increase in temperature, allowing for greater flexibility and movement. Additionally, warming up improves nerve impulse velocity rather than decreasing it; quicker nerve impulse transmission enhances the communication between the brain and muscles, contributing to better coordination and reaction times. Lastly, nerve receptor sensitivity increases during a warm-up, not decreases, making the body more responsive to stimuli. Therefore, the increase in muscle blood flow is a significant and beneficial outcome of incorporating warm-up activities into a training regimen.