How to work out what your heart rate should be during HIIT

Most will now agree that HIIT is one of, if not the, most efficient type of training to improve health, build lean muscle, burn fat and increase endurance. But how do you know if you’re doing it correctly? That you’re actually pushing yourself into the zone that will speed up your metabolic rate and keep you burning fat for many hours post workout. 

Fit squad DXB’s Daniel Wells explains the calculations you need to work out where you need to be during your sessions…


First and foremost, you need to calculate your Maximum Heart Rate (MHR). The quickest and most simple way to do this is to subtract your age from 220. I have used my own data for all of the below calculations, so my MHR would be 188:

220 - Age: 32 = 188 (MHR)


Second of all you will need to work out your Resting Heart Rate (RHR) and this can be done by simply putting two fingers across the inside of your left wrist and counting the total beats in one minute. This is best done in the morning and definitely pre-caffeine. 

My RHR is 65


Next you will need to workout your Heart Rate Reserve (HRH) and to do this you need to subtract your RHR from your MHR. Below I have used my own data as an example of the calculation: 

220 - Age: 32 = 188 (MHR) - 65 (RHR) = 123 (HRR)


Now that you have your HRR you’re ready to workout your heart rate training zone for HIIT. During the high intensity periods of your HIIT workout you need to be hitting somewhere between 70% and 90% of your HRR for optimal results. I am going to use the above data from my previous calculation and workout 70% and 90% of my HRR

70% = 123 (HRR) - 30% = 86.1

90% = 123 (HRR) - 10% = 110.7


The final step to give me my heart rate training zone for HIIT is to add my RHR to these percentages. Below is an example using the previous figures.

70% = 123 (HRR) - 30% = 86.1 + 65 = 151.1

90% = 123 (HRR) - 10% = 110.7 + 65 = 175.7


So, during the high intensity periods of my session I am looking to reach a minimum heart rate of 151.1 and a maximum of 175.7. It’s so important to know this information because if you’re under it’s not HIIT and you will not receive the benefits, and if it’s over you could well be doing more harm than good. 

Once you have your numbers use a heart rate monitor to measure you’re hitting the right rate. If you don’t have one, a good indiction that you’re at the right heart rate is your deep, rapid breathing and only managing to speak a few words at a time. 

If you’re new to HIIT, you may want to start at 70% to 80% effort instead or speak to a personal trainer for advice. 


All our Fit Squad DXB trainers can guide you with your HIIT sessions. Get in touch by calling or WhatsApping us on +971 55 542 7231 or emailing us at


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