Look at your collected lab data, what happens to the heart rate as the R-R interval decreases? A. The heart rate decreases. B. The heart rate increases. C. The heart rate stays the same.

When the R-R interval decreases, it indicates that the time between heartbeats is getting shorter. Consequently, this means the heart is pumping faster, leading to an increase in heart rate. So, you can confidently select B. The heart rate increases. In various physical activities or during stress, our body's demand for oxygen rises, prompting the heart to quicken its pace. This response showcases the incredible efficiency of the cardiovascular system in adapting to changing needs, reflecting how our bodies work harmoniously with physical demands!