- Its often the case where it feels like im running low on energy and maybe Bevel’s energy bank supports this, but I am able to push through and keep going. On Bevel, as you get closer to 0% , the energy bank decreases at a decreasing rate and tends to 0 (it never reaches it), which is not physiologically accurate - you don’t disproportionately decrease your energy expenditure by resuming the same activities just because you are tired, if anything energy is used less efficiently - less efficient anaerobic dominance, neuromuscular fatigue, poor form - as you are more tired - running 10k while tired would drain you the same if not more than if you were energised.

- Example: I was very tired one evening, energy bank was low (around 11%) - however I was able to hike all night up a volcano and stay awake all of the following day, but I didn’t collapse or anything (i.e, what the language of 0% energy bank/body battery implies), and my body battery was at 1% for the majority of the 36 hours.

- So either, 1. we find out when your body is able to run off of adrenaline or whatever the biological explanation there is for it to keep going (which I doubt your apple watch can do - and body battery in itself is not a verified scientific concept), or 2. we use an idea like borrowed energy - energy usage below 0%, which will then subtract from future energy banks, or have an accurate biological collateral impact on future energy banks (find some biological proof) which is more realistic, as then your body has to do extra catch up on reenergising you - its a pointer to the user that you are now draining your body’s energy in an unsustainable and costly way.

- Other apps like Peakwatch give much more generous body batteries, but it always feels inaccurate in day to day life because it would say I end the day on 50% battery despite feeling tired, and that I would always be charged to 99-100% the next day regardless of how unrestful the sleep is

Barometric pressure changes and reduced sunlight affects of weather should be used in some way to calculate energy drain and strain targets, considering energy tends to run lower on such days. Previous day's hydration levels should also do this, particularly on hot sunny days, as insufficient water consumption results in lower energy the following day.

Last night my hrv was so high my energy bank filled to 100% despite getting less total sleep and less deep sleep than I need. Yesterday my energy bank and strain target range did not match how I felt. Please weigh sleep data more heavily, at least with regards to overnight energy bank charging. Dropping deep sleep time plus rising sleep debt amount should counteract unusually high hrv more. My energy bank was 100%, but probably should have been closer to 80% this morning. Thank you.