Grade by Grade
B. Active Living / C. Movement Competence · Active Living and Movement: Train Smart, Respond Well, Play with Purpose

Find Your Zone: Heart Rate, Intensity and Daily Activity

B2 A1.1 A1.2About 40 minutes
Learning goals
  • I can take part in at least 20 minutes of moderate to vigorous activity each day with a warm-up and cool-down.
  • I can estimate my maximum heart rate and work out my own moderate and vigorous heart-rate zones.
  • I can check my intensity with heart rate, the talk test and how I feel, and adjust my effort.
  • I can use activity and a calm cool-down to help manage stress.

Words to know

intensity
How hard your body is working during an activity.
maximum heart rate
The highest number of times your heart can beat in a minute. A common estimate is 220 minus your age.
target heart-rate zone
A range of heart rates that matches the intensity you want, like moderate or vigorous.
resting heart rate
Your heart rate when you have been sitting or lying still and relaxed for a while.
pulse
The beat you feel in an artery each time your heart pumps blood.
interval training
Switching between harder work periods and easier recovery periods.

Remember from Grade 7

In Grade 7 you designed warm-ups (raise, mobilize, activity-specific, build up), main parts and cool-downs, and you checked your effort with the talk test, the 0 to 10 effort scale and your 15-second pulse count × 4.

This year you will use a new tool: your own heart-rate zones. They help you know whether you are really working at a moderate or vigorous level.

Hook: are you really working?

Two friends go for a 20-minute "run". One jogs, chats the whole time and never gets out of breath. The other runs so fast she has to stop after 4 minutes.

Neither one got 20 minutes of moderate to vigorous activity. The first was mostly too easy; the second was too hard to keep going. Knowing your zone helps you pick the right pace.

Two runners jogging side by side on a paved lakeside path in a green park, with a city skyline across the water.
A steady pace you can keep for 20 minutes or more, like these two runners on a lakeside path, is where heart-rate zones help most. Too easy or too hard, and you miss your moderate to vigorous minutes. AI-generated image

Step 1: Estimate your maximum heart rate

A common way to estimate maximum heart rate is:

Maximum heart rate ≈ 220 − your age

For a 13-year-old: 220 − 13 = 207 beats per minute.

This is only an estimate. Real maximum heart rates vary from person to person by quite a lot. Never try to reach your maximum on purpose. You use this number only to work out your zones.

Step 2: Work out your zones

One guideline used by health organizations is:

  • Moderate intensity: about 64% to 76% of maximum heart rate.
  • Vigorous intensity: about 77% to 93% of maximum heart rate.

To find a percentage of a number, change the percent to a decimal and multiply. For example, 64% of 207 = 0.64 × 207 = 132.48, which rounds to 132.

lightmoderatevigorous132157159193207Heart rate in beats per minute, age 13 (max about 207)
Heart-rate zones for a 13-year-old (estimated maximum 207). The middle box shows moderate (about 132 to 157) and the next box shows vigorous (about 159 to 193). The numbers are estimates.
Way to checkModerateVigorousGood for
Heart-rate zoneAbout 64% to 76% of maxAbout 77% to 93% of maxChecking with numbers
Talk testYou can talk, but not singOnly a few words at a timeQuick checks while moving
Effort scale (0 to 10)About 5 to 6About 7 to 8Knowing how it feels to you
Use more than one check. Heart rate can also be raised by heat, excitement, nervousness or caffeine, so listen to your body too.

Taking your pulse

  1. Stop moving and find your pulse right away, because it starts to drop within seconds.
  2. Use your index and middle fingers (not your thumb, which has its own pulse) on the thumb side of your wrist, or gently on the side of your neck. Never press hard on the neck.
  3. Count the beats for 15 seconds and multiply by 4, or count for 10 seconds and multiply by 6.

Building a great 20 minutes

  • Warm-up (5 to 10 min): raise your heart rate gradually toward the low end of your moderate zone.
  • Main part (at least 20 min): stay in your moderate or vigorous zones. Intervals work well: for example, 1 minute fast skipping, 1 minute marching, repeated.
  • Cool-down (5 to 10 min): walk until your heart rate drops, then hold static stretches and breathe slowly.

Moving to calm down

Activity is one of the best tools for stress. When you feel tense or worried, a brisk walk or a few minutes of skipping can help. Then, during your cool-down, try box breathing: breathe in for 4 counts, hold for 4, out for 4, hold for 4. Notice how your heart rate and your feelings settle together.

Worked example

Let's find Nadia's zones

Nadia is 14. Work out her estimated maximum heart rate and her moderate and vigorous zones. Round to the nearest whole number.

  1. Maximum: 220 − 14 = 206 beats per minute.
  2. Moderate low end: 0.64 × 206 = 131.84 → 132. Moderate high end: 0.76 × 206 = 156.56 → 157.
  3. Vigorous low end: 0.77 × 206 = 158.62 → 159. Vigorous high end: 0.93 × 206 = 191.58 → 192.
  4. Check: the numbers go up in order and stay below 206, so they make sense.

Nadia's moderate zone is about 132 to 157 and her vigorous zone is about 159 to 192 beats per minute.

Worked example

Let's read the numbers and adjust

Ethan is 13 (moderate about 132 to 157, vigorous about 159 to 193). During a bike ride he counts 30 beats in 15 seconds. Later, on a hill, he counts 44 beats in 15 seconds. What zone was he in each time?

  1. First check: 30 × 4 = 120 beats per minute. That is below 132, so it's light. He should pedal a bit faster.
  2. Second check: 44 × 4 = 176 beats per minute. That is between 159 and 193, so it's vigorous.
  3. Plan: after the hill, he eases off a little so he can keep going for the full ride.

120 bpm: light (speed up). 176 bpm: vigorous (good for short efforts like hills).

Hands-on activity

Zone check interval session

You need: a timer, a notebook and pencil, running shoes, a skipping rope (optional), and a safe space indoors or in a yard or park.

Warm up (6 minutes): 2 minutes brisk walking or marching, then arm circles, leg swings (hold a wall), walking lunges, and 4 short jogs of 10 seconds each.

  1. Write your estimated maximum and your zones at the top of your page.
  2. Main part (20 minutes): repeat this 4-minute block 5 times: 2 minutes of moderate work (jogging, steady skipping, dancing) + 1 minute of vigorous work (fast skipping, quick-feet running, step-ups on a bottom stair) + 1 minute of easy marching.
  3. Take a 15-second pulse at the end of the vigorous minute in rounds 1, 3 and 5. Multiply by 4. Write it down with your talk-test result and effort number.
  4. Cool down (5 to 8 minutes): walk slowly, then hold stretches for calves, quadriceps, hamstrings and chest for 20 to 30 seconds each. Finish with box breathing.
  5. Reflect: Did your heart rate reach your vigorous zone? Did your talk test and effort number agree with your heart rate?

Safety: Stop and tell a grown-up if you feel chest pain, dizziness, faintness or unusual shortness of breath. If you have asthma or a heart condition, follow your doctor's advice and keep your inhaler or medication nearby. Use stairs only on the bottom step, holding a railing. Drink water.

vigorousmoderateeasy15 s pulse15 s pulse15 s pulse06101418222632minWarm-upMain part: 5 blocks × 4 min = 20 minCool-downeach block: 2 min moderate + 1 min vigorous + 1 min easy
The zone check interval session as a timeline. The line steps up and down through the moderate and vigorous bands, and the dots show when to take a 15-second pulse (end of the vigorous minute in rounds 1, 3 and 5). It shows a pattern, not real heart-rate numbers.
Just for fun

Funny but true: your heart beats roughly 100 000 times a day without ever asking for a day off, a snack break or a better playlist. The least you can do is check in on it with a pulse count once in a while.

Your turn

1

Estimate the maximum heart rate of a 12-year-old.

2

What percentages of maximum heart rate give moderate intensity in the guideline from this lesson? What about vigorous?

3

You count 38 beats in 15 seconds. What is your heart rate in beats per minute?

4

Why should you take your pulse right away after stopping?

5

Which fingers should you use to take your pulse, and why not your thumb?

6

Name three parts of a daily activity session.

7

Give two reasons your heart rate might be high even though you aren't working hard.

More practice: warm-up

1

220 − 13 = ?

2

You count 25 beats in 10 seconds. Multiply by what to get beats per minute? What is the answer?

3

In the talk test, can you sing during vigorous activity?

4

What is interval training?

5

Name one breathing technique for a calm cool-down.

More practice: on your own

1

Work out the moderate zone for a 15-year-old. Round to whole numbers.

2

Maya (13, vigorous zone about 159 to 193) counts 36 beats in 15 seconds after sprinting. Is she in her vigorous zone?

3

Explain why 220 − age is called an estimate.

4

Plan a 20-minute interval main part using only a skipping rope and a timer. Show that it adds up to 20 minutes.

5

You feel angry after an argument. Explain how a walk and a cool-down could help.

Challenge

1

Ali is 13. His heart rates in a soccer game (taken from 15-second counts) were 33, 41, 47 and 29. Convert each to beats per minute and say which zone each is in (moderate about 132 to 157, vigorous about 159 to 193).

2

A 13-year-old's vigorous zone runs from about 159 to 193. If she counts for 15 seconds, between which two counts should she land to be in this zone?

3

Your talk test says "moderate" but your heart rate says "vigorous". Give two possible reasons and what you would do.

Check your understanding

Quiz

1.

What is the estimated maximum heart rate of a 13-year-old?

2.

You count 40 beats in 15 seconds. Your heart rate is:

3.

In the guideline from this lesson, moderate intensity is about:

4.

Where should you take your pulse?

5.

Which belongs in a cool-down?

6.

Why use more than one way to check intensity?

For parents and teachers

Big idea: In Grade 8, students take part in at least 20 minutes of moderate to vigorous activity each day with a proper warm-up and cool-down, and learn to monitor intensity. This lesson adds estimated heart-rate zones (220 − age, then percentages) to the talk test and effort scale they used in Grade 7.

How to help at home:

  • Practise taking a pulse together after climbing stairs or a brisk walk.
  • Help with the percentage maths (0.64 × 207) if needed: it links to Grade 8 math.
  • Do the interval session together and compare how the talk test feels.

Common difficulties:

  • Treating 220 − age as exact. It's an estimate; individuals vary.
  • Counting too late. The pulse drops fast after stopping.
  • Pressing too hard on the neck. Teach the wrist pulse first.

Safety: If your child has asthma, a heart condition, or another health concern, follow your health-care provider's advice about intensity. Chest pain, fainting or dizziness during exercise always means stop and get medical advice.

Social-emotional learning: Using activity and breathing to calm down builds stress management and coping (A1.2) and helps with managing emotions (A1.1).