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Now that you’ve been introduced the science behind Heart Rate Variability (HRV) and what makes it such a powerful tool, it’s time to explore exactly how you can take full advantage of it.


In our Guide to Heart Rate Variability, we discussed how HRV is controlled by the autonomic nervous system. In short, HRV is regulated by the autonomic nervous system (ANS) and its sympathetic (SNS) and parasympathetic branches (PNS). HRV is commonly accepted as a non-invasive marker of autonomic nervous system activity.

The parasympathetic branch is characterized as the rest and digest system that makes the body power down and recover after a period of sympathetic activation, aka an exhausting workout or stressful day¹.

The sympathetic branch activates the stress hormones to increase your heart rate and decrease HRV, which is needed during exercise and mentally or physically stressful situations¹.

The back-and-forth between these two branches inspired our team at Loops to develop the Daily Outlook feature, informing users exactly what their body needs each day, by just wearing their Apple Watch. 


When our team white-boarded the initial concept of Loops we spent a great deal of time discussing the core pillars that would define our user experience. The reoccurring theme in these discussions always started and ended with one sentence “make it simple”. From then on, we set out on a mission to take a concept, that at its core seemed like you needed a science degree to understand, and turn it into something that anyone could use. What we noticed with other HRV Platforms was that they take an HRV measurement and combine it into an algorithm that gives you an arbitrary score to demonstrate what your body could be feeling on that day. We felt this caused a major disconnect in understanding exactly what a single HRV reading means for your day ahead and how yesterday could have played a role in the outcome of today’s reading. This led us to develop our favourite feature, the Daily Outlook.

The Daily Outlook feature was built using learnings from extensive research proving the effectiveness of using daily HRV to prescribe a training regimen². We then built our own unique research-backed methodology to simply tell you what activities are best for your body on any given day. Each Daily Outlook tells you how well you’ve recovered from the previous day³ and exactly what your performance capabilities are for the day ahead. 


Before I continue, you’ve probably figured out that everything covered in these early blogs has been set up to lay the foundation of Loops.  The reoccurring concepts of Heart Rate Variability (HRV), HRV Baseline Range and the Autonomic Nervous System all work side-by-side to provide you with an end result: your Daily Outlook.

Let’s Recap:

  • Loops uses HRV as a non-invasive indication of what branch (Sympathetic and Parasympathetic) is activated within one’s nervous system.
  • Since everyone is different, we must calibrate your HRV Baseline Range which allows us to calculate your own unique “normal” – and gives us something to compare your progress back to!
  • Low HRV values can account mostly for sympathetic activity, while High HRV values may account for parasympathetic activity.

Simply put, your Daily Outlook represents where your morning HRV reading falls relative to your Baseline Range. However, there are two caveats to remember:

  • Your HRV Baseline Range is completely personalized to you and your current health level. For example, an HRV measurement of 120ms could mean two completely different outlooks for different users.
  • An individual HRV reading won’t always produce the same Daily Outlook. Your Daily Outlook will depend on where you are in your health journey. For example, a reading of 120ms one day might give you a Max Performance Day, but the same reading of 120ms two weeks later might give you a Relaxation Day.

Now that I’ve explained the science behind HRV and how you can use your baseline to interpret what’s going on internally with your Daily Outlook, it’s time to show you all outlooks you might receive. Each Daily Outlook has been named based on where your HRV reading falls relative to your baseline, according to our research.

Max Performance Day

This outlook occurs when your most recent HRV reading falls within the parasympathetic range of your HRV baseline. This means your body has successfully recovered and possibly even made fitness gains. On your Max Performance days, you’re ready to push your limits and perform optimally – so go for that PR!

Relaxation Day

This outlook occurs when your morning HRV reading is much lower than your HRV Baseline Range. This may mean that your body is under significant strain from common life stressors or a high intensity workout. When in this category, we recommend activating your Parasympathetic Nervous System to restore balance by getting rest, staying hydrated and practicing calming activities such as yoga or meditation.

Active Recovery Day

This outlook occurs when your morning HRV reading is within your HRV Baseline Range. When this happens, it means that your body’s recovery response has been activated, but you can still perform light exercise efficiently. This benefits your body by allowing you to continually make fitness gains while avoiding taking a complete rest day.

Rest Day

This outlook occurs when your morning HRV reading falls below your HRV Baseline Range, which is a sign that your body needs full recovery from a stressful event or activity. When this happens, your body is telling you to slow down so it can restore itself back to optimal, faster and more effectively.


  1. Adjei Tricia, von Rosenberg Wilhelm, Nakamura Takashi, Chanwimalueang Theerasak, Mandic Danilo P. The ClassA Framework: HRV Based Assessment of SNS and PNS Dynamics Without LF-HF Controversies, Frontiers in Physiology, 10, 2019.
  2. Javaloyes A, Sarabia JM, Lamberts RP, Moya-Ramon M. Training Prescription Guided by Heart Rate Variability in Cycling. Int J Sports Physiol Perform. 2018 May 29:1-28.
  3. Kiviniemi AM, Hautala AJ, Kinnunen H, Tulppo MP. Endurance training guided individually by daily heart rate variability measurements. Eur J Appl Physiol. 2007 Dec;101(6):743-51.