DIY Stethoscope: Step-by-step guide for your budding doctor 

Do you have an aspiring doctor at home? Well, a DIY stethoscope might be an activity he will love. Here is how to do it.  

What you’ll need 

• Duct tape 
• A pair of scissors 
• Plastic funnel 
• A cardboard tube (for example from paper-towel roll)  
• Stopwatch (to count seconds) 
• A volunteer who can exercise 

How to 
Help your child follow these easy steps for this DIY activity.  

• For the first step, have your child to put the narrow end of the funnel into the cardboard tube. 
• Next, ask them to tape the funnel and the cardboard tube together using the duct tape and scissors. Instruct them to make sure there are no visible gaps or spaces where they are taped together.  
• Believe it or not, the stethoscope like structure is ready. Now, all your child needs is a volunteer to test his or her DIY tool.  
• The youngsters can play doctor by listening to heartbeats. For this, ask them to place the funnel end on the left side of the volunteer’s chest while listening through the hole at the end of the cardboard tube. The goal is to keep the funnel flat against the volunteer’s chest, once at rest, and once after he or she is done exercising for a minute.  

Using a stethoscope 
When a person is at rest for a few minutes, listen to the heartbeat and count how many times it beats with a span of 10 seconds. Now multiply this number by 6 to get the resting heart rate of the person in beats per minute (bpm). Similarly, ask the same person to exercise for a minute, be it jumping jacks or running in one place. After one minute, immediately listen to the heartbeat for 10 seconds and do the calculation like before. The heart rate will automatically be a lot faster after exercising as compared to when it was at rest.  

When a person exercises, his or her body needs more oxygen, which is why, the heart beats faster and the heart rate enhances. So, the volunteer’s heart rate will rise in comparison to his or her resting heart rate. However, heart rates of individuals who exercise regularly will not enhance as much during exercise. This is because daily exercise strengthens the heart and it doesn’t need to put in the extra effort to help the body perform the same amount of exercise.