Skip to main content
Whoop

Why is my Strain 0.0?

Your strain score is strictly based on your heart rate data and the amount of time spent in each heart rate zone. 

Unlike counting steps, in order to accrue Strain, you must have an elevated heart rate for a sustained period of time. Within that elevated heart rate, there is a minimum heart rate-reserve threshold in order for you to receive Strain. If the minimum heart rate reserve threshold hasn't been met, you will not begin to accrue Strain for the day.  This is very common early in the day and if you are taking a Rest Day or Active Recovery Day.   
 

The minimum heart rate required to start accumulating Strain is 30% of your Heart Rate Reserve + your Resting Heart Rate. The equation for that heart rate threshold is RHR + .3(Heart Rate Reserve). Heart Rate Reserve is calculated by subtracting your Resting Heart Rate from your Max Heart Rate but after doing so you have to add your RHR to your HRR to get the number needed for Strain accrual.

HRR = Max HR - RHR
Minimum HR Needed to Accrue Strain = RHR + .3(HRR)

Screen Shot 2022-01-31 at 4.51.11 PM (1).png

Screen Shot 2020-08-22 at 8.50.38 AM.png

In this example, your heart rate would have to exceed 95 bpm for a sustained period of time in order for you to begin accruing Strain.  

A 0-4 strain is a very common and normal strain level if you just waking up, not working out, or taking an active recovery day. This does not mean that you are not active, but that your heart rate is not very elevated. This is why you are likely to see a low Strain for the day.

As you are working out more, your body will adapt to new Strain and training levels so your heart rate threshold is likely to change. It is common to see an increase in strain threshold since your heart can take on more with less exertion over time. 

For more information on Strain check out these articles, WHOOP Strain and Max Heart Rate Training Zones

  • Was this article helpful?