just to be a pain in the butt,
for medium its actually 0.000327, and 0.0008077 for high. its not much, but as you should always round DOWN to nearest half a point and most of the time you are not working at as high a rate as you think you are, its best to be precise otherwise you end up having an inaccurate reading. you are also best to assume medium intensity for most of your heavy exercise unless you are completely sure you could not have put an ounce more effort into your session.
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