RT5 Measuring Intensity

Throughout the course we talk about effort and intensity levels in relation to how hard you should be working. If you do not have a lot of experience with physical training this can sometimes be hard to measure. In order to help you can refer to this table which explains the RPE Scale.

RPE (Rate of Perceived Exertion) Scale

RPE Scale HR Zone Heart Rate Description
0 N/A Recovery Resting heart rate Complete rest.
1 N/A Recovery Very easy Light walking.
2 N/A Recovery Very easy Light walking.
3 N/A Recovery Very easy Walking.
4 Zone 1 Still easy Maybe starting to sweat.
5 Zone 2 Starting to work You can feel your HR rise.
6 Zone 2 Working but sustainable Can talk in full sentences.
7 Zone 3 Strong effort Breathing laboured, but can still maintain pace for a long time without slowing.
8 Zone 4 Race pace This is your lactate threshold / your best effort for one hour.
9 Zone 5 10k run effort Very hard.
10 Zone 5 5k run effort Cannot hold effort for more than a minute or two.

It can also be very useful to know what your heart rate (HR) is, but you will need a HR monitor for this. You can pick up a basic version for between £30 – £50. This is not essential so please do not feel like you need one.

Defining maximum heart rate (HR Max) is easy: it’s the highest number of beats per minute your heart can pump under maximum stress.

There are several methods to calculate or estimate your maximum heart rate.

Method 1: 220 – Your Age

Your maximum heart rate can be estimated from the commonly used formula: 220 minus age. While a good starting point, research has shown that this formula is not perfectly accurate for all people, especially for people who have been fit for many years or for older people.

Method 2: Laboratory Test

If you want the most accurate way of determining your maximum heart rate, you should have your HR max clinically measured. This is something you will need to have done in a laboratory. The two most common ways are the maximal treadmill and bicycle stress tests. These laboratory tests are usually supervised by a cardiologist or exercise physiologist.

Method 3: The Field Test

Besides estimations and tests, you can determine your maximum heart rate by putting on your running shoes, firing up your heart rate monitor and heading out into the real world.

You won’t need fancy laboratory equipment for the field test but you’ll still get an accurate and personal estimation of your maximum heart rate. The premise is simple: you warm up properly and then do an exercise that brings you close to your maximum effort.

NOTE: Doing a maximum heart rate field test while unprepared is a surefire way to end up in maximum distress. If you are unsure, consult your physician before undertaking the test.

Do this field test with a training partner. Use a heart rate monitor and note the highest heart rate you can reach. This is your maximum heart rate.

  1. Warm up for 15 minutes on a flat surface. Build up to your usual training pace.
  2. Choose a hill that will take more than 2 minutes to climb. Run up the hill once, building to as hard a pace as you would be able to hold for 20 minutes. Return to the base of the hill.
  3. Run up the hill again. Get your heart going as hard as you can to be able to just about hold it there for 15 minutes. Observe your highest heart rate on the display. Your HR max is approximately 10 beats higher than the now-noted value.
  4. Run back down the hill. Allow your heart rate to drop 30 – 40 beats per minute from where it was.
  5. Run up the hill once again at a pace that you can only hold for 1 minute. Try to run halfway up the hill. Observe your highest heart rate. This brings you close to your maximum heart rate.
  6. Make sure you cool-down for a minimum of 10 minutes.

Heart Rate Zones

Once you know your Max HR you can use the following table to work out your zones:

Intensity Aprox % Max HR Breathing Feeling Training Benefit
Zone 1

(The Guilty Zone)

50 – 60% Nose breathing Super easy effort. It’s so easy that you should feel ‘guilty’ when you are done. You don’t think you went hard enough; it didn’t feel like a workout; you don’t think there was any benefit because it felt too easy. If you have these types of thoughts after a Zone 1 workout, then you are doing it right. This is the very low intensity zone. Training at this intensity will boost your recovery and get you ready to train in the higher heart rate zones.
Zone 2

(The Conversation Zone)

60 – 70% Nose breathing Pretty easy as well, at least in the beginning. But you should feel as though you have to work if you’ve been doing this several hours. You should be able to hold a conversation for the duration of this workout, and I mean being able to talk in full sentences, not one- or two-word gasps. This is the zone that improves your general endurance: your body will get better at oxidising (burning) fat and your muscular fitness will increase along with your capillary density.
Zone 3

(The Grey Zone)

70 – 80% Deep & steady You typically aren’t going easy enough to get the benefits of a nice easy effort and you aren’t going hard enough to get the benefits of a ‘Race Pace’ workout. You can talk in one- to two-word answers. This is also sometimes called the NBZ – “No Benefit Zone.” Running in Zone 3 is especially effective for improving the efficiency of blood circulation in the heart and skeletal muscles. This is the zone in which lactic acid starts building up in your bloodstream.
Zone 4

(The Race Pace Zone)

80 – 90% Short sentences This is where you have burning legs and lungs and you can’t keep the effort up for much more than an hour. (By definition, your threshold is an effort you can manage for one hour). You know when you are in Zone 4 as your breathing is labored, your arms and legs get very heavy and all you want to do is stop. If you train at this intensity, you’ll improve your speed endurance. Your body will get better at using carbohydrates for energy and you’ll be able to withstand higher levels of lactic acid in your blood for longer.
Zone 5

(The Max Intensity Zone)

90 – 100% No talking These efforts may last from a few seconds to maybe five or six minutes. This zone is beneficial if you are doing a lot of racing that has hard but very short efforts, such as bike racing or racing short events on the track in running. Your heart and your blood and respiratory system will be working at their maximal capacity. Lactic acid will build up in your blood and after a few minutes you won’t be able to continue at this intensity.


Lessons in this course: