Heart Rate Lab Report

The purpose of this lab was to determine how different conditions could affect one's heart rate. In the life of a human, the heart beats approximately forty-five million times per year varying based off of factors like age, gender, physical activity level (1). Furthermore, throughout the course of a day, the heart can vary in its heart rate from a number of different environmental changes such as prolonged standing, altered breathing (inhale vs. exhale), and jolts of excitement such as being startled. Relating to the heart rate of an individual is their blood pressure which is regulated by baroreceptors in the body that are located throughout the aortic arch and carotid
Arteries (2). The baroreceptors of the body act as essentially pressure sensors that and operate under negative feedback in order to maintain the arterial pressure (and thus blood pressure) of the body. For example, if a decrease in the arterial pressure occurs, baroreceptors will decrease their firing rate activating the cardioacceleratory and vasomotor centers and inhibiting the cardioinhibitory center. This
Readings were initially taken on the subject while he/she was sitting down in order to get a baseline reading. ECG readings were then taken while the subject was standing up, inhaling extendedly, exhaling extendedly, and while being startled. The ECG recordings were done with a Bio-Pac unit and data was analyzed using Microsoft excel.

Results The results of the experiment from Table 1 demonstrate a general trend of increasing HR for inhaling and standing when compared to baseline data while exhaled and startled HRs were lower than baseline HR. Figure 1 on the other hand demonstrates a trend that in both males and females, HR always increased from sitting to standing. Males however, did show a larger HR at rest and when standing compared to females.