My hypothesis is if you increase your exercise intensity, then your heart rate will become higher, because your heart will be working harder to get blood to your muscles. The more often I exercise, I predict my heart rate will go down over time, because the heart muscle will become stronger.

My brother and I have started going to the gym. I want to know how exercise is affecting my heart. I noticed that some people at the gym are breathing faster than others, so some hearts are working harder than others but your heart keeps pumping no matter what. I also found that an interesting book about the heart by Joesph Midthun that tells a lot of facts and talks about the Circulatory System. With people that have more intensive workouts the four parts of there heart are working harder by the increasing exercise. In each contraction of your heart, it sends blood out to your body as your red blood cells deliver oxygen. As the heart muscle pumps it gets a little more efficient because your heart is a muscle and it get stronger with exercise. The long-term effect there are benefits to exercising an example is lower resting heart rate. During exercise, your body may need four times the amount of blood because your muscles need more oxygen and fuel. This experiment was fun to do, and I would love to do it again.

 

Background Research Sources and Notes:

“The building blocks of science: The Circulatory System” By Josph Midthun.

-Your heart works as a pump

-Your heart works even at rest

-Your heart has two side and four chambers, Right Atrium, left Atrium, Right Ventricle and the Left Ventricle.

-The right side of the heart doesn’t have much oxygen

-The left side of the heart has oxygen rich-blood that pumps to your rest of your body

-The heart is really two pumps, one pump sends blood up to the lungs, thee other pump sends it out to your body and muscles.

-Exercise makes your heart more efficient at pumping.

 

“The Circulatory System where do I get my Energy” By Chris Oxlade

-A normal heart is about the size of a clenched fist

-when the heart muscles contract that is a heartbeat

-Lub Dub sound when you listen to the heart is really the two valves in between the chambers

-Your heart is the center of the circulatory system

-Your heart will never get tired

-On average, a heart beats 70 times a minute, 4200 times a hour and about 100,000 times a day

-Your heart is a crucial organ

 

"How Does Exercise affect your heart, and what are the benefits?" Feb 17, 2016. 

https://www.nebh.org/blog/how-does-exercise-affect-your-heart-and-what-are-the-benefits/

 

"Why does your heart rate increase during exercise?"

https://www.afibamerica.com/why-does-your-heart-rate-increase-during-exercise/

 

Cardiac Output

https://myhealth.alberta.ca/Health/Pages/conditions.aspx?hwid=tx4080abc&lang=en-ca#:~:text=Generally%20speaking%2C%20your%20heart%20beats,brain%20and%20other%20vital%20organs.

 

Vital Signs in Children

https://myhealth.alberta.ca/Health/pages/conditions.aspx?hwid=abo2987

 

 

 

Variables

Controlled variables:  The subject (myself), method of tracking heart rate (Fitbit), duration of exercise (five minutes) and rest in between exercises (15 minutes).

Manipulated Variable:  The manipulated variable in my experiment is the intensity of the exercise. I was able to change the intensity of the exercise by changing the speed and incline of the treadmill.

Responding Variable: My responding variable is my heartrate. I considered three options; stethoscope, measuring with my wrist and my fitbit. The fitbit was the easiest option because it was the most consistent. The stethoscope and measuring my wrist was inaccurate because it was easy to miss a beat. To double check the fitbit was correct, I borrowed a hospital grade pulse oximeter to check.

Procedure:

 

1. For each trial that I did, I spent 15 minutes at rest to get my heart rate at a resting point.

2. For exercise #1 (low intensity), I walked on the treadmill at incline = 0 speed = 1, this wasn’t very hard. I was able to speak full sentences during this exercise. I measured my heart rate after 5 minutes of walking on the treadmill.

3. For exercise #2 (moderate intensity), I jogged on the treadmill at the incline = 3 speed = 3, this was more difficult then exercise 1. I was still able to speak short answers. After I was done jogging on the treadmill I recorded my heart rate.

4. For exercise #3 (high intensity), I sprinted on the treadmill at the incline = 5 speed = 5 this was very hard, more harder then 1 and 2 combined, I could not speak when I was sprinting. At thee end of the five minutes I was able to record my heart rate.

5. I recorded my heart rate over 9 days and put it all into a table.

6.  I took an average of my heart rate for each of my activities.

7. see bar graph for results.

Observations:

See bar graph results

Observations:

In the first 4 graphs I made, I recorded my heart rate (beats per minute) and compared each day of exercise. In all of graphs, I found that there was no trend. My heart rate did not show a trend comparing each day compared to each other. For each category of exercise my heart rate was similar or stayed within a range.

 

The last graph shows my average heart rate over the different days. Then I compared all the intensities against each other. I did notice a trend. As intensity of the exercise increase, my heart rate increased.

 

 

Please refur to attachments for bar graphs are in there.

 

Conclusion:

 

For my first part of my hypothesis was proven correct.

If you increase your exercise intensity, then your heart rate will become higher, because your heart will be working harder to get blood to your muscles.

See my final bar graph.

 

For second part of my hypothesis, it was inconclusive.

The more often I exercise, I predict my heart rate will go down over time, because the heart muscle will become strong.

My heart rate did not go down over the 9 days. My heart rate stayed around the same rate for the intensity of the exercise. After speaking with Dr. Shannon Rzyck (Internal Medicine doctor, at FMC) she suggested next time I measure my heart rate and exercise over a long period of time 6 months or a year.       

Application:

 This experiment does not have a widespread application. For my own benefit, it would be good to compare my heart rate if I continued to exercise regularly. I could compare my heart rate from month 1 to months and years in the future. It would also would be useful to compare my heart rate to other exercises, like weightlifting. This experiment world have better application if I had many 11 year olds test subjects, and tracked there heart rate.

Extension:

There are lots of ways to build on this experiment. Hear of some of my ideas:

            -Compare 11-year-olds to other age groups while exercising

            -Heart rate of athletes vs non athletes

            -Treadmill running vs outdoor running

            -Treadmill vs elliptical

            -Measuring other vital signs like blood pressure and breathing right

            -different heart rate monitors

            -You could change the time of exercise

Here are the following sources of error in my experiment: 

~The speed on my treadmill my not have been accurate

~My Fitbit my have not been accurate in recording my heart rate

~My personal conditioning

 

 

 

Refur to reserch all citations are there.

I would like to thank my mom for geting me a heart rate moniter.