The tests that you do in your laboratory enable you to see how cardiovascular fitness is affected by various conditions. The following questions will help reinforce your understanding of circulatory system function and fitness.

1. Why does increased physical activity raise heart rate?

2. Why is heart rate lower in an individual who does aerobic exercise regularly?

3. Why do some people feel faint when they go quickly from lying down to standing?

4. How and why does heart rate change with body position?

5. From your study of the circulatory system, how would you describe a "fit" individual?

Continue to Lab Quiz I.