One school of thought with regards exercise goes as follows: as hard as you’re pushing yourself at any one time, push yourself more. This old-school, bro-code style is at best simplistic, and at worst actively detrimental. You want a varied approach to your training, including varied levels of intensity, both to continue to explore new avenues for your physical fitness and to give your body some time to recover.
Without this time, you will likely over train and burn out fairly quickly, stopping your exercise journey dead in its tracks. No matter your goal- hypertrophy, endurance, weight loss or myriad others- you won’t achieve them laid up like this.
In addition, knowledge is power: a detailed overview of your biometrics can only ever be helpful in your training. With a heartrate monitor, you can see exactly what that HIIT class is doing for you, how your body is responding on heavy lifting days, and what various other forms of exercise do for you.
There are various methods you can use to monitor how hard you are working. RPE and max percentages are quite common in the lifting world. However, for a reliable, universal benchmark, there are few measurable bio-indicators as trusty or worthwhile as your heart rate.
With this in mind, it’s a good idea to get yourself a heart rate monitor.
You can set yourself target heart rates and see how well you measure up. For instance, in a calmer session, you can aim to get to around 60% max heart rate. Tougher exercise will have you aiming more towards 80-90%. Live feedback from a heartrate monitor can allow you to change tempos as you go, making sure that you’re always at the level you want.
Your heart rate
To make the most of the information a heart rate monitor gives you, start by figuring out your maximum heart rate. Many devices will estimate your maximum heart rate for you when you set up your profile, but if you want to check it out yourself, McCall recommends the Tanaka method to give you a good estimate:
Maximum heart rate (MHR) = 208 - (0.7 x your age)
You can use this to check out where your heart rate should be across various intensities.
If your heart rate in any given exercise is between .6-.7 of your MHR, you’re performing low intensity cardio. This will include activities like walking or light jogging.
f your heart rate is between .7-.85 MRH, this will be moderate cardio. Running, swimming and working a lighter punch bag are good examples of moderate cardio. Weightlifting with shorter rest periods will usually keep you around here, though it isn’t strictly considered ‘cardio.’
This leaves high-intensity cardio, which will be anything above .85 x MRH. Circuit training, giant sets, boxing heavily, HIIT classes and sprinting will all likely take you into this category.
Heart rate and controlling your BMI
Knowing your exercise intensity will allow you to better control your diet. You should have consulted a Body Mass Index (BMI) calculator prior to any training regime in which weight loss, gain or recomposition is required. The Harris-Benedict formula will allow you to work out your Basal Metabolic Rate (BMR) with regards how many calories your body needs to do the exercise it is doing. If you find that you’re only training at 50% max heartrate, but that you’ve recorded yourself as very active in a BMR reading, your BMI isn’t likely to go down. Conversely, if you’re trying to gain weight, are regularly training at 80%, and you’ve only put yourself down as lightly active, your BMI isn’t going to climb.
So, whether you’re simply curious about what’s happening in your body as you exercise, or you want to be able to precisely gauge your metabolic needs in order to manipulate your BMI, or you want to be able to keep yourself in the training area you want, a heart rate monitor is a good investment.