The Comparison of Responses of the Same Level of Exercise on the Heart Rate and Blood Pressure of Boys and Girls

By: Joyce Acen

Introduction:

Question:

Will the girls’ and boys’ responses to the same level of exercise differ on its effect to their heart rate and blood pressure?

Background:

The functions of the human cardiopulmonary physiology can be broken down into the circulatory system and the respiratory system. The main goal of these two systems is to maintain homeostasis. Homeostasis can be described as a type of condition where the internal continuity of an individual has to keep steadiness, regardless of any external changes from the outside environment. (Biozone, 252) External changes from the outside environment may include factors such as excitement, stress, exercise, diet, and many more. Exercise can be carried out because the human body can endure a high level of exercise during a prolonged period of time. (Biozone, 226) In this experiment, we will focus on how exercise, in particular, affects the cardiopulmonary physiology of girls and boys.

Exercise places strenuous activity on the human body. When an individual exercises, the blood flow must level up to the demands being made on the individual’s muscles, heart and lungs. (Biozone, 225) Blood flow increases so that the blood does not clot and so that it can supply oxygen and all of the necessary nutrients to the tissues and organs. An essential reason to why oxygen and nutrients are needed is because they are the ingredients that allow the heart to continue pumping blood throughout the venous, arterial, and portal systems. (Biozone, 225) The heart is one of the main organs involved in the human cardiopulmonary physiology because it keeps blood moving through the contraction of its valves. More specifically, the right side of the heart pumps blood to the lungs so that it can get oxygenated, while the left side of the heart pumps blood to the body.

When an individual exercises, the generated heat must be dissipated, oxygen demands must increase, and waste products must be produced. If we imagine that an individual has begun exercising, the oxygen uptake increases because there is a higher demand for energy. Oxygen is the ultimate source of energy that allows ATP to be generated. More ATP must be made in order for homeostasis to be maintained. After a prolonged period of exercise, lactic acid accumulation begins to occur in the tissues of the body because energy for oxygen uptake can no longer be supplied after a certain period of time of exercise. (Biozone, 308) When the individual ends exercising, it takes time for the oxygen uptake to return to its resting level because the lactic acid that had accumulated in the tissues must be broken down into CO2 and H2O. The individual breathes deeply during this time because heavy breaths of oxygen must be taken in for the lactic acid to be broken down.

A process which allows human beings to take in oxygen and remove carbon dioxide would be gas exchange. The set of mechanisms within this process allow cellular respiration to occur. Cellular respiration results in the release of energy that comes from organic compounds. These organic compounds generate waste materials that must be removed through exhalation. (Biozone, 191)

Hypothesis:

Since the human body is put under strenuous physical activity during exercise, it will require faster circulation and respiration throughout the body. Because one of the factors that affect the cardiopulmonary function is gender, if we test girls and boys under the same level exercise, then the boys will have higher blood pressure and a higher heart rate and will recover faster because they can supply their bodies with oxygen at a quicker rate than girls.

 

Overview of Experiment:

Through this lab, the girls’ and boys’ responses to the same level of exercise will be observed and compared to find similarities and differences in its effects to their heart rate and blood pressure. The hypothesis will be tested through the method of having measured the individuals’ blood pressure with the sphygmomanometer.

Materials and Methods:

            The scientist must have his/her breathing rates measured under different conditions with the use of a stopwatch, and a sphygmomanometer. To begin experimentation, the individual being tested must have his/her resting blood pressure measured. To do this, the sphygmomanometer must be placed above the elbow so that the wire connected to the monitor and the pressure cuff goes over the brachial artery. The cuff should be inflated to about 150mm Hg each time a measurement it taken. Once the resting blood pressure has been found, the individual being tested should begin exercising for 1 minute without a break. Immediately after exercise, the individual should have his blood pressure measured. Then every 2 minutes after the individual has stopped exercising, the blood pressure should also be measured until a total of 10 minutes has passed.

Results:

The overall results showed that the boys had higher systolic and diastolic pressures, while their heart rate pulses were not significantly different from the data results of the girls’ heart rate pulses.

The results for the boys indicated that their initial systolic pressure was at 121 mm Hg, their diastolic pressure was at 76 mm Hg, and their heart rate pulse was at 75 beats per minute (bpm). Their highest systolic pressure was 146 mm Hg at 0 minutes, 89 mm Hg for the diastolic pressure at 0 minutes, and 119 bpm for the pulse at 0 minutes. 0 minutes represents the immediate time after exercise was finished. The boys’ lowest systolic pressure was 121mm Hg at 6 minutes, 70 mm Hg for the diastolic pressure at 8 minutes, and 71 bpm for the pulse at 4 minutes. The recovery rate was measured by finding the difference between immediate exercise and 2 minutes. The boys’ systolic pressure recovery rate decreased by 11 mm Hg, their diastolic pressure decreased by 2 mm Hg, and their pulse rate decreased by 43bpm.

The results for the girls showed that their initial systolic pressure was 104 mm Hg, 67 mm Hg for their diastolic pressure, and 72 bpm for their pulse rate. Their highest recordings came in at 0 minutes, immediately after exercise. They were 128 mm Hg for the systolic pressure, 82 mm Hg for the diastolic pressure, and 120bpm for the pulse rate. Their lowest data points were consistent with the basal time because the systolic pressure was 104 mm Hg at their basal time (before exercise), their lowest diastolic pressure was 67 mm Hg at their basal time, and their lowest pulse time was 72bpm at the basal time. The girls’ systolic pressure recovery rate was decreased by 7 mm Hg, their diastolic pressure recovery rate was decreased by 6 mm Hg, and their pulse rate decreased by 39bpm.

boys and girls heart rate

 

This table summarizes the averages of systolic pressure, diastolic pressure, and the heart rate pulses for both genders.

Discussion:

The hypothesis for this laboratory report stated that if we test girls and boys under the same level exercise, then the boys will have higher blood pressure and a higher heart rate and will recover faster because they can supply their bodies with oxygen at a quicker rate than girls.

Looking at the data results, the boys did have higher systolic and diastolic pressures than the girls, but their pulse recordings were fairly similar to that of the girls’ pulse data records. The boys’ systolic pressure was higher by about 20 mm Hg throughout each recording. The boy’s diastolic pressure was higher by about 5 to 10 mm Hg than that of girls.  But both genders’ pulse rates were ranged from 70bpm to 120bpm. As for the recovery rate, the data collected indicates that the difference rate after immediate exercise to 2 minutes was higher for the boys than for the girls because the decrease from the recordings after immediate exercise to 2 minutes was more extreme in mm Hg and in heart beats per minute for the boys. So overall, the data collected supports the hypothesis for the most part except for the statement made about the heart rate being higher for boys than for the girls. The hypothesis for the heart rate difference was incorrect because the assumption about the relationship between systolic and diastolic pressure was correlated to the heart rate pulse recordings.

One source stated that the effect of exercise on blood pressure will vary depending on factors such as gender (Sheryl R, 2010). Therefore, the results for the heart pulse rate conflict with the hypothesis because theoretically the heart rates for both genders should be somewhat different.

Some weaknesses identified within the experimental set would be inaccurate timing, and equal intensities of exercise among all students. Inaccurate timing seemed to be an issue because it was difficult to gather recordings exactly 2 minutes from every previous recording. This was a problem because the sphygmomanometer would sometimes automatically shut down causing a prolonged timing error between recordings. The intensity of exercise was not the same among all students which could have contributed to inaccurate data. Some students exercised harder for the 1st minute than others which made their systolic and diastolic pressures significantly higher.

Literature Cited:

Brainbridge-Smith, Lissa, Richard Allan, and Tracey Greenwood. “Energy and Exercise.” Print. Rpt. in Senior Biology 2 2009. 8th ed. BIOZONE International, 2008. 307-08. Print.

Brainbridge-Smith, Lissa, Tracey Greenwood, and Richard Allan. “Exercise and Blood Flow.” Print. Rpt. in Senior Biology 2 2009. 8th ed. BIOZONE International, 2008. 225-26. Print.

Greenwood, Tracey, Lissa Brainbridge-Smith, and Richard Allan. “Introduction to Gas Exchange.” Print. Rpt. in Senior Biology 2 2009. 8th ed. BIOZONE International, 2008. 191. Print.

R, Sheryl. “The Relationship Between Diastolic Blood Pressure and Exercise.” Find Health, Education, Science & Technology Articles, Reviews, How-To and Tech Tips At Bright Hub – Apply To Be A Writer Today! 3 May 2010. Web. 19 Feb. 2011. <http://www.brighthub.com/health/fitness/articles/41153.aspx>.