Calculating Training Intensities

This lesson covers the calculations required by the AQA GCSE PE specification (3.1.3) for determining training intensity. You need to know how to calculate maximum heart rate, training zones (aerobic and anaerobic), and how to use one rep max to set weight training intensity. These calculations are frequently tested in the exam.

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Maximum Heart Rate (Max HR)

The Formula

Maximum heart rate is the highest number of beats per minute your heart can achieve during maximum physical effort. It is estimated using the formula:

Max HR = 220 − age

Examples

Age	Calculation	Max HR
15 years	220 − 15	205 bpm
18 years	220 − 18	202 bpm
25 years	220 − 25	195 bpm
40 years	220 − 40	180 bpm
60 years	220 − 60	160 bpm

Key Points

• This is an estimate — actual max HR can vary between individuals of the same age.
• Max HR decreases with age because the heart becomes less able to beat at very high rates.
• It is used as the basis for calculating training zones (the specific heart rate ranges at which different types of training take effect).

Exam Tip: Always show your working in calculations. If the question says "a 16-year-old performer", write: Max HR = 220 − 16 = 204 bpm. Even if you make an arithmetic error, you can still gain marks for showing the correct method.

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Training Zones

Once you know the maximum heart rate, you can calculate the training zones — the ranges of heart rate at which specific physiological adaptations occur.

The Aerobic Training Zone (60–80% of Max HR)

The aerobic training zone is the heart rate range in which the body uses oxygen as the primary energy source. Training in this zone develops cardiovascular endurance.

Formula:

• Lower limit: Max HR × 0.60
• Upper limit: Max HR × 0.80

Example for a 16-year-old:

• Max HR = 220 − 16 = 204 bpm
• Lower limit: 204 × 0.60 = 122.4 bpm (round to 122 bpm)
• Upper limit: 204 × 0.80 = 163.2 bpm (round to 163 bpm)
• Aerobic training zone: 122–163 bpm

The Anaerobic Training Zone (80–90% of Max HR)

The anaerobic training zone is the heart rate range in which the body can no longer supply enough oxygen to meet the muscles' demands. The body starts to rely on anaerobic energy systems, and lactic acid builds up. Training in this zone develops speed, power, and the body's ability to tolerate lactic acid.

Formula:

• Lower limit: Max HR × 0.80
• Upper limit: Max HR × 0.90

Example for a 16-year-old:

• Max HR = 220 − 16 = 204 bpm
• Lower limit: 204 × 0.80 = 163.2 bpm (round to 163 bpm)
• Upper limit: 204 × 0.90 = 183.6 bpm (round to 184 bpm)
• Anaerobic training zone: 163–184 bpm

Training Zone Diagram

graph TD
    A["Maximum Heart Rate<br/>220 − age"] --> B["90% of Max HR"]
    A --> C["80% of Max HR"]
    A --> D["60% of Max HR"]

    B --- E["Anaerobic Zone<br/>80–90% Max HR<br/>Speed, Power, Lactic Acid Tolerance"]
    C --- E
    C --- F["Aerobic Zone<br/>60–80% Max HR<br/>Cardiovascular Endurance"]
    D --- F

    style A fill:#2c3e50,color:#fff
    style E fill:#e74c3c,color:#fff
    style F fill:#27ae60,color:#fff

Full Worked Example

Question: A 15-year-old netball player wants to improve her cardiovascular endurance. Calculate her aerobic training zone.

Answer:

1. Max HR = 220 − 15 = 205 bpm
2. Lower limit of aerobic zone = 205 × 0.60 = 123 bpm
3. Upper limit of aerobic zone = 205 × 0.80 = 164 bpm
4. Her aerobic training zone is 123–164 bpm.
5. She should train at a heart rate between 123 and 164 bpm to develop cardiovascular endurance.

Question: The same player wants to improve her anaerobic fitness for sprinting during games. Calculate her anaerobic training zone.

Answer:

1. Max HR = 205 bpm (already calculated)
2. Lower limit of anaerobic zone = 205 × 0.80 = 164 bpm
3. Upper limit of anaerobic zone = 205 × 0.90 = 184.5 bpm (round to 185 bpm)
4. Her anaerobic training zone is 164–185 bpm.

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Monitoring Intensity During Training

There are several ways to monitor whether a performer is training in the correct zone:

1. Heart Rate Monitors

• Electronic devices worn on the wrist or chest that display heart rate in real-time.
• Advantages: accurate, easy to read during exercise, can set alerts if heart rate goes above or below the target zone.
• Disadvantages: can be expensive, may be uncomfortable, technology can malfunction.

2. Manual Pulse Check

• The performer stops briefly and takes their pulse at the radial artery (wrist) or carotid artery (neck).
• Count the number of beats in 15 seconds and multiply by 4 to get beats per minute.
• Advantages: no equipment needed, can be done anywhere.
• Disadvantages: requires stopping exercise (which lowers heart rate immediately), less accurate than a heart rate monitor, can be difficult to find the pulse during exercise.

3. Rate of Perceived Exertion (RPE)

• A subjective scale (typically the Borg Scale, from 6–20 or a simplified 1–10 scale) where the performer rates how hard they feel they are working.
• An RPE of 12–14 on the Borg scale (6–20) roughly corresponds to the aerobic zone.
• An RPE of 15–17 roughly corresponds to the anaerobic zone.
• Advantages: no equipment needed, can be used during any activity.
• Disadvantages: subjective — what feels "hard" to one person may feel "moderate" to another.

4. Talk Test

• If the performer can hold a conversation during exercise, they are likely in the aerobic zone.
• If they can only speak in short phrases, they are approaching the anaerobic zone.
• If they cannot speak at all, they are working at or above the anaerobic threshold.

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One Rep Max and Weight Training Intensity

What Is One Rep Max (1RM)?

The one rep max (1RM) is the maximum weight a person can lift for one complete repetition with correct technique. It is used as a benchmark to set the intensity of weight training.

How to Estimate 1RM Without Testing

If it is not safe or practical to test a true 1RM (e.g., with beginners or young athletes), it can be estimated using the Epley formula:

Estimated 1RM = weight lifted × (1 + 0.0333 × number of reps)

Example: If a performer lifts 60 kg for 8 reps:

• Estimated 1RM = 60 × (1 + 0.0333 × 8)
• = 60 × (1 + 0.2664)
• = 60 × 1.2664
• = 76 kg (approximately)

Setting Weight Training Intensity

Once the 1RM is known, training intensity is set as a percentage:

Goal	Percentage of 1RM	Reps	Sets	Effect
Maximal strength	> 70%	4–8	3–5	Increases the maximum force a muscle can produce
Muscular endurance	< 70%	12–15	3	Increases the ability of muscles to sustain repeated contractions
Power	50–70%	3–6 (at speed)	3–5	Increases the rate of force production

Worked Example

Question: A rugby player has a one rep max of 100 kg for the bench press. Calculate the training weight for: (a) strength training; (b) muscular endurance training.

Answer:

(a) Strength training (>70% of 1RM):

• Training weight = 100 × 0.70 = 70 kg (minimum)
• He should lift at least 70 kg for 3 sets of 4–8 reps with 2–4 minutes rest between sets.

(b) Muscular endurance training (<70% of 1RM):

• Training weight = 100 × 0.70 = 70 kg (maximum)
• He should lift less than 70 kg (e.g., 50–65 kg) for 3 sets of 12–15 reps with 30–60 seconds rest between sets.

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Applying Progressive Overload to Intensity

Progressive overload can be applied through intensity in several ways:

Training Type	How to Apply Progressive Overload
Cardiovascular training	Increase the target heart rate within the zone (e.g., from 65% to 75% of max HR)
Weight training	Increase the weight lifted (e.g., from 70% to 75% of 1RM)
Interval training	Reduce the rest period or increase the intensity of work intervals
Circuit training	Increase the duration of each station or add more challenging exercises

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