How To Train With Heart Rate Zones
Many women in the SWEAT Community have fitness trackers or heart rate monitors to track their activity and heart rate during their workouts. One reason to measure your heart rate is that you need to exercise at a certain intensity to achieve specific health and fitness goals.
For example, if you’re doing fasted cardio, you might use a lower intensity training zone than if you’ve eaten.
Here’s what you need to know about the different heart rate zones you can target to reach your fitness goals.
- Why measure heart rate
- How to estimate your max heart rate
- What are heart rate zones?
- Low intensity
- Moderate intensity
- High intensity
- Maximum effort
- Heart rate zone for LISS
- What to do if you don't have a heart rate tracker
- Target your training with heart rate zones
Why do we measure heart rate?
When you exercise, you strengthen your muscles, including your heart. Just like the other muscles in your body, when you challenge your heart to work harder, it becomes stronger.
The harder you exercise, the more oxygen your muscles need to get energy. This means your heart pumps faster and harder!
Heart rate is measured in ‘beats per minute’.
Your resting heart rate (RHR) can indicate how physically fit you are. Generally speaking, a lower resting heart rate means your heart is more efficient — this is a good thing!
You can measure your resting heart rate by taking your pulse first thing in the morning when you wake up. Depending on your fitness level, the normal range is between 60-80 bpm.
Heart rate can be affected by stress, anxiety, posture, temperature and many other factors, so it can vary from day to day. If you have any concerns about your heart rate, check with your doctor.
How to estimate your max heart rate (MHR)
To get your maximum heart rate estimate, subtract your age from 220.
For example, if you are 27 years old, your estimated maximum heart rate will be 193 beats per minute (bpm).
This formula is just a guide1. Sometimes people can record a heart rate slightly higher than this during very intense activity.
What are the heart rate zones?
Heart rate zones are a percentage range of your maximum heart rate2. Each heart rate zone is a measure of intensity with a corresponding Rate of Perceived Exertion and is best suited for different fitness goals.
Low intensity 50-70% MHR
When walking at a moderate to brisk pace, your heart rate should be in the low-intensity zone.
This zone is ideal for warming up and cooling down before and after your workouts.
Using our example of a 27-year old female, this will be a heart rate of 96-135bpm.
Training at this intensity helps to improve blood flow and circulation to the muscles used. You should be able to carry on a conversation at this intensity.
Moderate intensity 70-80% MHR
When training in this heart rate zone, you will be breathing harder and find it a little harder to talk.
Training at a moderate intensity can increase your endurance, lung capacity and the efficiency of your cardiovascular system.
For a 27-year old, this is around 135-155 bpm. You would usually be running, cycling or swimming at a solid pace to achieve this intensity.
On average, your body uses equal amounts of energy from fat and carbohydrate when training in this zone.
High-intensity 80-90% MHR
Also known as your “anaerobic threshold training zone” exercising at this intensity can improve your VO2 max and your ability to recycle lactate into energy - which means you can go harder for longer.
VO2 max is the maximum rate at which your heart, lungs and muscles can effectively use oxygen during exercise.
For a 27-year old woman, this is a heart rate between 155-174bpm.
This zone is the upper limit of your physical capacity.
Training at 80-90% of your heart rate can increase endurance and burn calories faster than during lower intensity exercise.
Maximum effort 90-100% MHR
Sometimes referred to as the “red zone”, you’ll usually only be able to sustain this level of effort for a short time, such as in an all-out sprint.
For our example 27-year old female, this maximal heart rate zone will be 174-193bpm.
When you first start exercising, you might not be able to go hard enough to get into this zone, and that’s perfectly okay!
For more advanced exercisers, you’ll ideally get into this zone at the toughest part of a HIIT workout.
What should your heart rate be for LISS?
Your target heart rate for LISS (or Low Intensity Steady State Cardio) workouts should be 40-70% of your maximum heart rate. This would put your target heart rate in the the low-intensity zone.
For most people, this could be a brisk walk, gentle cycling, swimming, rowing or similar.
To get the maximum benefits from LISS, you should aim to do the session in one block of time rather than several smaller blocks.
However, if the only way you can fit in your LISS is by breaking it up across the day, this is still much better than skipping it altogether!
All of the SWEAT programs have at least one low-intensity cardio session to complete each week.
What if I don’t have a heart rate tracker?
If you don’t have a smartwatch or fitness tracker that shows your heart rate, don’t worry! There is another way to measure the intensity of your workouts called “rating of perceived exertion” or RPE.
A good guide to your RPE is how hard you are breathing or how intense you rate the exercise on a scale of 1-10.
- 0 = nothing at all (reading a book, watching Netflix).
- 0.5 = Just noticeable (tying shoelaces)
- 1 = Very light exertion (chores like folding washing)
- 2 = Light exertion (walking through the supermarket)
- 3 = Moderate exertion (brisk walk)
- 4 = Putting in some effort
- 5 = You can feel the effort
- 6 = Getting more intense (running or cycling that gets the heart-pounding and fast breathing.)
- 7 = Hard but sustainable
- 8 = Very hard
- 9 = Extremely hard to sustain
- 10 = Can only sustain this effort for a few seconds (an all-out sprint)
For those women using RPE, your LISS sessions should be done at an intensity of about three or “moderate exertion”. If you are doing a HIIT workout, you should reach an intensity of eight during your working periods.
Use your heart rate zones to target your training
Using heart rate zones or your perceived rate of exertion can help you to focus your training to achieve specific fitness goals.
Ideally, you’ll include a variety of workouts across different intensity zones throughout your week!
When doing high-intensity interval training, you should allow a rest day before doing another high-intensity session. This allows your body to recover and adapt to the training before your next session.
Use the days between high-intensity or resistance training to do a low-intensity steady-state (LISS) workout or take a full rest day.
Following a fitness program designed by a personal trainer can help you to get the right balance through each of the key training zones each week.
Do you track your heart rate or rely on perceived exertion to monitor your training? Let us know in the comments!
1 Zhu N, Suarez-Lopez JR, Sidney S, et al. Longitudinal examination of age-predicted symptom-limited exercise maximum HR. Med Sci Sports Exerc. 2010;42(8):1519–1527. doi:10.1249/MSS.0b013e3181cf8242
2. K. Norton et al. / Journal of Science and Medicine in Sport 13 (2010) 496–502.
* Results may vary. Strict adherence to the nutrition and exercise guide are required for best results.