One or more additional sensors that do not measure hydration level of the user can be coupled to a hydration sensing element to determine the amount of fluid consumption for {HEAD ~ the user} in {TAIL ~ different conditions} 
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One or more additional sensors that do not measure hydration level of the user can be coupled to a hydration sensing element to determine the amount of fluid consumption for { HEAD ~ the user } in { TAIL ~ different conditions }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL