How can heart rate zone training help your running?
Heart rate (HR) training is focused on your heart beats per minute, rather than your pace. It can help your performance, fitness, and can reduce the risk of injury!
Step 1: Find your max heart rate
Calculating your approximate personal maximum heart rate can be using an age based formula (220 - your age = Max heart rate), but this does not take into account factors like genetic makeup so can be inaccurate.
The most accurate way to find your max heart rate at home is to track your heart rate during workouts over a few weeks, and push yourself to what feels like 100% of your effort at several points throughout the workouts. You’ll want to sustain this effort for around a minute if you can. Look back over your stats and look for your highest ever heart rate.
You can also have a stress test in a lab, but this involves specialist input and kit which will not be accessible to everyone.
It’s also helpful to be aware of your resting heart rate - when you are doing no activity at all. This tends to be somewhere between 60 - 100 bpm, but can vary based on a number of factors. The fitter you are, the lower your heart rate tends to be, as the heart is more efficient with pumping blood around the body with each beat.
Step 2: Work out heart rate training zones
There are 5 “zones” when training with your heart rate, based on a percentage of your maximum heart rate. It is helpful to roughly understand what your heart rate would be when training in each zone, so that you can work more accurately.
Zone 1: 50 - 60%
Zone 2: 60 - 70%
Zone 3: 70 - 80%
Zone 4: 80 - 90%
Zone 5: 90 - 100%
Tracking recovery heart rate is helpful to keep track of your fitness too. This is the time it takes for your heart rate to return to normal after a period of high intensity exercise. The fitter you are, the quicker the heart will recover.
Step 3: Work out which zone you need to train in
Zone 1: "Easy" - Warm-ups and cool-downs
Zone 2: "Comfortable" - Endurance training, used for the bulk of running training. You should be able to sustain this effort for many miles and be able to chat a little bit with a workout partner.
Zone 3: "Uncomfortable" - Tempo run (these are good for building up speed and strength). Your body will need to start breaking down glucose for energy, and working anaerobically (without oxygen). This will create a lactic acid build up, which you may start to feel in your muscles.
Zone 4: "Intense" - Speed endurance and improving your VO2 max (the maximum rate of oxygen your body is able to use for exercise before it changes to glucose).
Zone 5: "Flat Out" - Sprint interval training. You won’t be able to train at this level for longer than a couple of minutes due to the lactic acid build up in your muscles.
Step 4: Use a fitness watch to monitor zones
Depending on your goals, you can use these zones to ensure that your workout is in line with your training objectives, and you aren't working too hard for your longer runs.
Some watches will even monitor these zones for you, to make it easier for you to know where you are at with your training.
You’ll want to spend around 50% of your time in Zone 2 for an endurance programme. In this zone, muscle fibres use oxygen to produce energy by breaking down fats. In higher zones, the oxygen cannot get to the muscles quickly enough, so glycogen stores are used, and lactic acid is produced.
Beware the Zone 3 plateau!
Many runners will fall into the trap of running long distances at Zone 3, as they fix on the miles/km per minute, and think that running harder will lead to better fitness. However, because Zone 3 has some lactic acid response, it is above aerobic pace and therefore too hard to allow for day to day recovery. Because it is not hard enough to be pushing VO2 max, you will not elicit a desirable physical benefit either, so you are left feeling exhausted without any positive adaptations.
By running at a slower level more regularly, you are training your body to turn oxygen into energy more efficiently and building your aerobic endurance. This means fatigue will not set in as fast and you will be able to run for longer without feeling exhausted.
Step 5: Create your training programme
Depending on what you are training for, you can now create a running programme based around your heart rate zones. If you are training for a shorter run, you will want to incorporate some of the higher heart rate zones into your plan, as it will be your lactate threshold and VO2 max that you want to work on.
If you are training for a longer event, you will want more time in Zone 2 to ensure a recovery response, and increase your fat burning ability.
However, in both circumstances, you should have high intensity days, and these need to be HARD! This will get your body more efficient at burning carbohydrates for energy and help you to mitigage lactic acid build up, which will create optimal performance.