You’ve been working out solidly for weeks on end, but you still feel like it’s a chore to complete the circuit.
Never mind that, you’re disappointed with your results. Surely you should see more improvements after putting in this amount of effort, right?
While you’ve done the warm up, completed the perfect number of reps at each station and taken the time to stretch after each and every session, there’s something you may be missing…
It has nothing to do with the gym equipment you use, nor does it involve the type of workout you do. Instead, it has to do with one of your essential organs: your heart.
Have you ever measured your heart rate?
If you haven’t taken your heart rate into account when you exercise, you could be losing out on important information that allows you to push yourself harder when it’s necessary, and then slow down at other times as a means to optimize the overall impact of your workout.
Your heart beat during exercise is far more important than a simple means to pump blood around your body. It can show you whether you really put in as much effort into your workouts as you think you do.
To understand the link between heart rate and exercise and how you can use it to help optimize your routine, you must first understand the heart rate zones and how to calculate them1:
- Maximum heart rate: Calculate this by subtracting your age from 220. For example, if you’re 30 years old, your maximum heart rate should never exceed 190.
- Resting heart rate: First thing in the morning, before you get out of bed, place your index and middle finger on the inside of your wrist below the fleshy part of your thumb, and count the number of beats in 60 seconds. Do this on 3-4 consecutive mornings to ensure accuracy.
- Heart rate reserve: This is the difference you get when you subtract your resting heart rate from your maximum heart rate. For example, if your resting heart rate is 70 and your maximum is 190, your heart rate reserve is 120 beat per minute.
- Fat burning heart rate zone: To find this, begin by calculating 50-75% of your heart rate reserve. Following with our example, 50% of 120 is 60 and 75% of 120 is 84. Next, add your resting heart rate (ex. 70) to each number, which determines the heart rate zone for aerobic fat burning will be between 130-154 beats a minute.
- Aerobic fitness heart rate zone: First, start by calculating 75-85% of your heart rate reserve (ex. 120), which works out to 90 and 102. Next, add your resting heart rate (ex. 70) to get 160-172 beats per minute.
Now, here’s the thing… even though there’s a fat burning heart rate zone, the way it has been proposed to work is somewhat of a myth.
You can’t simply keep working out in the fat burning zone and expect to lose a ton of weight - but, unfortunately, the body just doesn’t work that way. Instead, the way to really benefit from exercise and lose weight while improving your overall fitness levels is to maximise on these heart rate zones2.
Exercise intensity and interval training
The reason many people who only run on a treadmill or do cardio exercises don’t see great improvements in their form is because they are likely not pushing their intensity enough, and are likely burning fewer calories than they perceive. If you often workout in a circuit, the same could be happening to you, where your intensity is just not high enough during periods of work - that’s where heart rate monitoring comes in3!
Put simply, the more intense your workout, the more fat you’ll burn and the fitter you’ll become. You can’t, however, continue to exercise flat out every time. It will only leave you exhausted, or worse, injured.
So, you need to cycle through high and low intensity periods to boost energy expenditure (which burns more calories) and allow for recovery (which is when muscle-building takes place). The best way to do so is to take part in interval type training while monitoring your heart rate4,5.
Interval training for weight loss and fitness
Whether you like to run or do a circuit-type workout, you can turn anything into an interval training session!
If running is your go-to, pump up the intensity to reach your aerobic heart rate zone, in order to optimize aerobic fitness. Then, alternate this zone with recovery periods where your heart rate is in the fat burning zone. This method also means you’ll burn more calories in less amount of time compared to pounding the pavement for hours at a slow and steady pace.
If you opt for circuit training, again aim to push yourself to achieve your aerobic heart rate zone, followed by recovering for a short time between exercises.
For strength training, it may not always be possible to reach your aerobic heart rate zone - however, you can definitely make adjustments to increase the intensity of strength training. Mixing it up with skipping rope, box jumps, short sprints or rowing in between sets will significantly increase your heart rate.
Overall, whatever your preference for daily workouts, monitoring your heart rate is one of the best ways to get the most out of it. As you become fitter and stronger, you can further increase your intensity and redo your heart rate calculations to follow along with your body6,7,8.
Once you begin monitoring heart rate, you may be surprised at how much harder you will push yourself to reach specific zones - and, even more surprised at the results you’ll see and feel because of it!
- Target Heart Rate and Estimated Maximum Heart Rate, Centers for Disease Control website.
- Buchheit M. Monitoring training status with HR measures: do all roads lead to Rome? Front Physiol. 2014;5:73.
- Borresen, J., & Lambert, M. The quantification of training load, the training response and the effect on performance. Sports Med. 2009;39(9):779-95.
- Borresen, J, & Lambert, M. Changes in heart rate recovery in response to acute changes in training load. Eur J Appl Physiol. 2007;101:503–11.
- Nelson, M., et al. Maximal rate of increase in heart rate during the rest-exercise transition tracks reductions in exercise performance when training load is increased. J Sci Med Sport. 2014;17:129–33.
- Thomson, R., et al. Effect of acute exercise-induced fatigue on maximal rate of heart rate increase during submaximal cycling. Res Sports Med. 2015.
- Borresen, J., & Lambert, M. Autonomic control of heart rate during and after exercise : measurements and implications for monitoring training status. Sports Med. 2008;38(8):633-46.
- Plews, D., et al. Training adaptation and heart rate variability in elite endurance athletes: opening the door to effective monitoring. Sports Med. 2013;43:773–81.