Medicine ClinicalVital Signs: Numbers That Show How Your Body Is Doing
Medi stands in a bright school nurse's office, pressing two fingers gently to a stuffed animal's wrist and watching a large clock on the wall, counting beats with a focused, curious expression while a thermometer and a chart of normal numbers sit on the desk nearby.
- Identify the three main vital signs: heart rate, breathing rate, and body temperature.
- Explain what each vital sign measures and why it matters for health.
- Compare normal vital sign ranges for children with values that are too high or too low.
- Predict whether a given vital sign number is inside or outside the normal range.
- Calculate a heart rate by counting beats for a set time and multiplying.
Key terms
- vital sign
- a number showing how your body works
- heart rate
- how many times your heart beats per minute
- breathing rate
- how many breaths you take each minute
- pulse
- the beat you feel where blood flows
Your Body's Dashboard
Think of your body like a car with a dashboard of gauges. Your body has its own dashboard too, called vital signs, and vital means important for life. The three main ones are heart rate, breathing rate, and body temperature. These numbers tell us how well your heart, lungs, and body are working, just like gauges tell a driver how the car is doing.
Counting Heart and Breaths
Your heart is a pump that pushes blood with oxygen all around your body. We count how many times it beats in one minute, and a healthy child beats about 70 to 110 times per minute. Every breath brings fresh oxygen into your lungs, and a healthy child breathes about 18 to 25 times per minute. When you run, both numbers go up to give your muscles more oxygen.
Body Heat and Fever
Your body makes heat to keep all its jobs running, and normal body temperature is about 37 degrees Celsius, which is 98.6 degrees Fahrenheit. When germs invade, your body raises its temperature to fight them, and that is called a fever. A temperature above 38 degrees Celsius is a fever. If a number is inside its normal range, your body is likely working well.
Worked examples
Count beats for thirty seconds
- Count your heartbeats for 30 seconds and get 40 beats.
- Thirty seconds is half a minute, so multiply by 2.
- 40 times 2 equals 80 beats per minute.
Answer: 80 beats per minute, which is inside the normal range of 70 to 110.
Is 130 beats per minute at rest normal
- Find the normal range for a child at rest: 70 to 110.
- Compare 130 to the range; it is higher than 110.
- A number above the range means it is too high.
Answer: 130 at rest is too high, which is a signal to check on the body.
Activity
Sort each vital sign reading into the correct bucket: Normal, Too High, or Too Low for a healthy child at rest.
Practice
If you count 35 beats in 30 seconds, how many per minute?
Is a temperature of 39.2 degrees Celsius a fever or normal?
Common mistakes to avoid
- Running gives you a feverA fever comes from germs or illness, not from normal exercise.
- Heart rate needs hospital machinesYou can measure heart rate simply by feeling your pulse and counting.
Check your understanding
A child at rest has a heart rate of 55 beats per minute. The normal range for children is 70–110 beats per minute. What does this number most likely mean?
Your friend says: "I have a fever because I ran really fast, so my body temperature went up just like my heart rate did." Is your friend correct?
You count your own heartbeats for 30 seconds and get 40 beats. How many beats per minute is that, and is it in the normal range for a child (70–110 bpm)?
Recap
The three main vital signs are heart rate, breathing rate, and body temperature, and each one tells us how your body is working. Counting beats and breaths and checking temperature shows if a number is inside the healthy range or outside it.
Reflect
Which vital sign would you most like to measure yourself?