Grade by Grade
A–B. Active Living and Movement Competence · Active Living and Movement: Train with Purpose, Play with Strategy

Keep It Going: Continuous, Interval and Circuit Training

A2.1 1.1About 70 minutes
Learning goals
  • I can participate regularly in sustained moderate to vigorous physical activity for at least 20 minutes, to the best of my ability.
  • I can explain continuous training, interval training, fartlek and continuous circuit training.
  • I can design a continuous circuit that keeps my heart rate in my target zone for 20 minutes or more.
  • I can calculate work-to-rest ratios and total session time, and monitor my intensity while I train.

Words to know

continuous training
Steady activity without rest breaks, such as a 25-minute jog, swim or ski at a moderate intensity.
interval training
Training that alternates harder work periods with easier recovery periods.
work-to-rest ratio
How long the work period is compared with the recovery period, such as 2:1 (60 s work, 30 s recovery).
continuous circuit training
Moving from station to station with little or no rest, so heart rate stays up for the whole circuit.
fartlek
A Swedish word meaning "speed play": continuous running with unplanned bursts of faster pace.
active recovery
Easy movement (walking, slow jogging) during the recovery part of an interval, instead of stopping.

Remember from Grade 9

In PPL1O you found your moderate and vigorous zones with the heart-rate reserve (Karvonen) method: target = (maximum − resting) × percent + resting, using about 40% to 59% for moderate and 60% to 89% for vigorous. You also checked intensity with the talk test and a 0 to 10 effort scale, and did a 20-minute fitness blast.

In Grade 10 you learn different ways to structure sustained activity, so you can choose the method that fits your goal, your space and the day.

Hook: the toughest race on snow

Cross-country skiing uses your legs, arms and core at the same time, often for an hour or more. Elite cross-country skiers have recorded some of the highest aerobic fitness scores ever measured in athletes.

You don't need to race to get the benefits. Skiing a local trail, swimming lengths at a community pool, playing a fast game of ultimate, or doing a continuous circuit in your basement can all keep your heart rate up for 20 minutes or more.

What A2.1 asks of you in Grade 10

Participate regularly in sustained moderate to vigorous physical activity to the best of your ability for a minimum of 20 minutes. The curriculum's Grade 10 examples:

  • continuous circuit training;
  • cross-country skiing;
  • ultimate;
  • swimming.

Notice that each example keeps you moving. "Sustained" means your heart rate stays in your target zone for the whole period, without long breaks.

Four ways to structure sustained activity

  1. Continuous training: one steady effort, usually moderate. Example: a 25-minute jog, swim or ski. Simple and great for building a base.
  2. Interval training: alternate work and recovery periods. Example: 1 minute hard, 1 minute easy, repeated 10 times. Recovery should be active (walk or easy jog) so the session stays sustained.
  3. Fartlek (speed play): a continuous run with unplanned faster bursts: "sprint to the next lamp post, then jog". Fun on trails and in parks.
  4. Continuous circuit training: move through stations (skipping, squats, push-ups) with only short transitions. Alternating cardio, legs, upper body and core lets one muscle group recover while your heart rate stays high.

Work-to-rest ratio compares work time to recovery time. 60 s work and 30 s recovery is 2:1; 30 s work and 30 s recovery is 1:1. A higher ratio (more work, less rest) is usually harder.

moderate zonevigorous zone60100140180051015202530minutesheart rate (bpm)continuous jogintervals: 1 min hard, 1 min easy
Two 30-minute sessions (typical patterns, not real data). The continuous jog stays steady in the moderate zone. The interval session rises into the vigorous zone during each hard minute and drops back to moderate during active recovery, so both keep heart rate in the target zones for the whole 20-minute main part.

Designing a continuous circuit

  1. Choose 6 to 10 stations, alternating cardio, legs, upper body and core.
  2. Set the timing: for example 45 s work + 15 s to move = 60 s per station.
  3. Work out the round time: stations × time per station.
  4. Choose the number of rounds so the total is at least 20 minutes (not counting warm-up and cool-down).
  5. Give options: easier and harder versions at each station (for example, push-ups on knees or on a wall).
  6. Monitor: do a quick pulse check (10 s × 6) or talk test at the end of each round.
1 skippingcardio2 squatslegs3 push-upsupper body4 mountainclimbers: core5 high kneescardio6 lungeslegs7 plankshoulder taps: core8 step-upscardio, legs60 s per station: 45 s work + 15 s to move8 stations = 8 min per round; 3 rounds = 24 min
A continuous circuit with 8 stations. Cardio stations (blue) are spread out so heart rate stays up; legs and upper body (green) and core (yellow) alternate so each muscle group can recover while you work another.
Worked example

Let's plan Theo's continuous circuit

Theo has 35 minutes. He needs a 5-minute warm-up and a 5-minute cool-down. His circuit has 8 stations of 45 s work + 15 s transition. How many full rounds can he do, and does he meet the 20-minute minimum?

  1. Time per station: 45 + 15 = 60 s = 1 min.
  2. Time per round: 8 stations × 1 min = 8 min.
  3. Time available for the main part: 35 − 5 − 5 = 25 min.
  4. Rounds: 25 ÷ 8 = 3.125, so 3 full rounds = 24 min (he can use the last minute for extra skipping).
  5. Work-to-rest ratio: 45 : 15 = 3:1. Transitions are active (walking to the next station), so heart rate stays up.

Theo can do 3 rounds (24 minutes), which meets the 20-minute minimum, with a 3:1 work-to-rest ratio.

Worked example

Let's check an interval session with heart rate

Priya (age 15, resting heart rate 65 bpm) does 10 intervals of 1 min fast jog / 1 min walk. Her Karvonen zones are moderate 121 to 148 bpm and vigorous 149 to 190 bpm. Her pulse checks: end of a fast minute: 27 beats in 10 s; end of a walk minute: 21 beats in 10 s. Is her session sustained MVPA?

  1. Check her zones: MHR = 220 − 15 = 205; HRR = 205 − 65 = 140. Moderate: 0.40 × 140 + 65 = 121; 0.59 × 140 + 65 = 147.6 → 148. Vigorous: 0.60 × 140 + 65 = 149; 0.89 × 140 + 65 = 189.6 → 190.
  2. Fast minute: 27 × 6 = 162 bpm: vigorous.
  3. Walk minute: 21 × 6 = 126 bpm: still moderate.
  4. Total time: 10 × (1 + 1) = 20 minutes, all in moderate or vigorous zones.

Yes. Her heart rate stayed at least moderate for the whole 20 minutes, because her recovery was active (walking briskly). Her work-to-rest ratio is 1:1.

Living skill: self-monitoring (1.1)

During sustained activity, check yourself every few minutes:

  • Too easy? (can sing, effort 3 or less) → shorten recovery, speed up, add arm movement.
  • In the zone? (can talk in short sentences, effort 5 to 8) → keep going.
  • Too hard? (can't speak, dizzy, effort 9 to 10) → slow down but keep moving; stop and tell an adult if you feel unwell.
Hands-on activity

24-minute continuous circuit with pulse checks

You need: running shoes, water, a timer (an interval-timer app helps), a skipping rope (optional), a sturdy low step (the bottom stair, holding the rail), a mat or towel, and a space about 2 m by 3 m indoors or in a yard.

Before: find your Karvonen zones (resting heart rate counted for 30 s × 2 after sitting quietly for 5 minutes).

Warm-up (5 min): RAMP: jog on the spot, glute bridges, leg swings, quick feet.

Circuit (3 rounds of 8 stations, 45 s work + 15 s move): skipping (or jumping jacks) → squats → push-ups (wall, knees or full) → mountain climbers → high knees → alternating lunges → plank with shoulder taps → step-ups.

Pulse checks: after each round, count for 10 s × 6 and record. Also record effort (0 to 10).

Cool-down (5 min): easy walk, then stretch calves, quadriceps, hamstrings, hips and chest for 20 to 30 s each.

Reflect: Were all three checks in your zones? Which station spiked your heart rate most?

Safety: clear the floor, use a non-slip surface, keep water nearby, and hold the rail on step-ups. Stop and tell an adult if you feel chest pain, dizziness or unusual shortness of breath. If you have asthma, keep your inhaler nearby.

Just for fun

Interval training is the only time a coach yells "Rest!" and the whole group cheers louder than they did for the last goal.

Your turn

1

Name the four Grade 10 curriculum examples of sustained MVPA.

2

What is the minimum time for sustained MVPA in A2.1?

3

Describe the difference between continuous and interval training.

4

Find the work-to-rest ratio: 40 s work, 20 s recovery.

5

A circuit has 10 stations of 50 s work + 10 s transition. How long is one round?

6

Why should a continuous circuit alternate muscle groups?

7

You count 23 beats in 10 seconds. What is your heart rate?

More practice: warm-up

1

What does fartlek mean?

2

What is active recovery?

3

Is a 25-minute steady swim continuous or interval training?

4

Find the ratio: 30 s work, 30 s recovery.

5

Give one easier option for push-ups.

More practice: on your own

1

Design a 6-station circuit (cardio, legs, upper body, core, cardio, legs) and give each station an exercise.

2

A 6-station circuit uses 40 s work + 20 s transition. How many rounds give at least 20 minutes?

3

During an interval walk, Priya's heart rate drops to 105 bpm (her moderate zone starts at 121). What should she change?

4

Explain why a game of ultimate can be sustained MVPA but slow-pitch softball usually isn't.

5

A 32-minute interval session has a 2:1 ratio with 2-minute work periods. How long is each recovery, and how many full work-recovery sets fit?

Challenge

1

Design a 20-minute fartlek run in a park that includes at least 5 bursts, and explain how it meets A2.1.

2

Compare a 1:1 interval session (1 min hard / 1 min easy) with a 3:1 session (90 s hard / 30 s easy), both 20 minutes long. Which is harder and why? Calculate total hard minutes in each.

3

Ben (resting 58 bpm, age 15) wants his interval recovery to stay at the low end of moderate (40% HRR). What heart rate is that, and what 10-second count?

Check your understanding

Quiz

1.

Which is a Grade 10 curriculum example of sustained MVPA?

2.

60 s of work and 30 s of recovery is a work-to-rest ratio of:

3.

A circuit has 8 stations of 60 s. How many rounds are needed for at least 20 minutes?

4.

Why use active recovery in intervals?

5.

Fartlek training is best described as:

6.

In a continuous circuit, alternating cardio, legs, upper body and core helps because:

For parents and teachers

Big idea: Expectation A2.1 asks students to take part regularly in sustained moderate to vigorous activity for at least 20 minutes. The Grade 10 examples are continuous circuit training, cross-country skiing, ultimate and swimming. This lesson teaches four ways to structure sustained activity and reuses the Grade 9 heart-rate reserve (Karvonen) method.

How to help at home:

  • Do the circuit together or time it for your teen; an interval-timer app is handy.
  • Look up public swim times or local ski or walking trails and plan a family session.
  • Ask your teen to explain the math: round time, number of rounds, work-to-rest ratio.

Common difficulties:

  • Counting warm-up and cool-down as part of the 20 minutes. The 20 minutes is the main part.
  • Stopping completely during recovery. Active recovery keeps it sustained.
  • Ratios written backwards. Work comes first: work : rest.

Safety: a clear, non-slip floor, water nearby, holding the rail on step-ups. Stop for chest pain, dizziness or unusual breathlessness, and follow medical advice for any heart or breathing condition.