Three horse-crazy friends in grade 5 decided to participate in their school’s science fair at Medford Elementary School in Minnesota. Jenna, Bella and Lily tossed around several cool ideas before deciding on, what for them, it was the perfect topic.
“It was something we all enjoyed, something like, horses! We knew right away that it would be a great experiment, and guess what, it was! We decided to do an experiment about how a horse’s heart rate changes with different levels of activities.”
The girls and Huck.
Once they decided on their subject they began gathering information. They researched about horse’s heart rates and found that the heart rate increases with activity. We learned that, “an adult horse has a resting heart rate of around 30 to 50 beats per minute (bpm). Walking, trotting, and cantering raise the rate to around 80, 130, and 180, respectively”
1. If you counted the number of heart beats in 15 seconds, what number would you multiply by to get the number of beats per minute?
2. If you counted the number of beats in 30 seconds, what number would you multiply by to get the number of beats per minute?
Their hypothesis for the project was that when the horse runs its heart rate would increase because it is using more energy and breathing heavier.
Science Talk – hypothesis: A hypothesis is an educated guess about how things work.
Next, they gathered supplies and materials.
They used Lily’s horse Huck (short for Huckleberry Fin). Other materials included in this project were, a lunge rope, halter, lead rope, note book, pencil, and a stethoscope. They got the stethoscope from their moms, two of whom are nurses.
Using the stethoscope to take Huck’s heart rate.
To begin their experiment, the girls recorded Huck’s resting heart rate by using the stethoscope to count the number of beats in 30 seconds. They repeated this 3 times to ensure accuracy.
They then recorded his heartbeat three separate times after he’d been walked for 30 seconds. They repeated this process at the trot, or in Huck’s case, the running walk, seeing as he is a Rocky Mountain Horse. Finally, they lunged Huck at a canter for 30 seconds and, using the stethoscope, recorded Huck’s heart rate three times.
They kept all the other variables the same, by using the same horse and testing all of the results on the same day.
Science Talk – resting heart rate: The resting heart rate is the heart rate when the horse has been at rest and not recently exercised.
Once they had their data collected, it was time to interpret the results.
The girls explained, “We chose a bar graph because we thought it was the best way to show the comparisons across the tests.”
3. Did the girls choose to use a horizontal or vertical bar graph?
4. What are the units for the heart rates shown in this bar graph?
5. What was Huck’s mean resting heart rate in beats per minute? Round your answer to the nearest ones.
6. Does Huck’s resting heart rate fall within the average range?
7. Is Huck’s average heart rate after trotting < or > his average resting heart rate?
The girls concluded in their written report, “Our hypothesis was proven correct. As Huck increased his speed and activity, his heart rate increased also!”
This project left them wondering, “Next time it would be fun to test several horses to see if we would have similar results. It would be interesting to see if riding them verses lunging them makes a difference on their heartbeats per minute.” Maybe next year they’ll put these questions to the test and come up with another great science project.
The girls were proud and excited to learn that their Heart Beats project was one of ten projects chosen from grades four to six to go on to the regional science fair competition at Minnesota State University, in Mankato! Good luck Jenna, Bella and Lily!
Horse Beats Science Project Answers:
1. If you counted the number of heart beats in 15 seconds, what number would you multiply by to get the number of beats per minute?
Answer: There are 60 seconds in one minute. 60 ÷ 15 = 4. You would multiply by 4 to get the number of beats in a minute.
2. If you counted the number of beats in 30 seconds, what number would you multiply by to get the number of beats per minute?
Answer: 60 ÷ 30 = 2. You would multiply by 2 to get the number of beats in a minute.
3. Did the girls choose to use a horizontal or vertical bar graph?
Answer: vertical
4. What are the units for the heart rates shown in this bar graph?
Answer: beats per 30 seconds
5. What was Huck’s mean resting heart rate in beats per minute? Round your answer to the nearest ones.
Answer:
Step 1: (28 + 32 + 28) ÷ 3 = 29.33
Step 2: 29.33 x 2 (there are two 30 second intervals in 1 minute) = 58.66. Huck’s average resting heart rate was 59 bpm.
6. Does Huck’s resting heart rate fall within the average range?
Answer: No. An average adult horse has a resting heart rate of around 30 to 50 beats per minute (bpm).
7. Is Huck’s average heart rate after trotting < or > his average resting heart rate?
Answer: > (greater than)
Common Core:
3.MD.B.3 – Interpret bar graphs
4.OA.A.2 – Divide by 2-digit numbers: word problems
5.NBT.B.7 – Multiply a decimal by a one-digit whole number
6.SP.A.3 – Calculate mean, median, mode, and range; Interpret charts to find mean, median, mode, and range
Photos:
All photos courtesy of Jenna, Bella and Lily
Here’s an easy way to make your own stethoscope for listening to a horse’s heartbeat: http://www.wikihow.com/Make-a-Homemade-Stethoscope