if you cant take your heart rate, a good way to recognize that your exercising efficiently is whether or not

Reason 1. It's Difficult to have a conversation Reason 2. You're experiencing some huffing and puffing Reason 3. you're gasping for breath.   D. your muscles are burning.

Explanation:

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fluid balance is an aspect of the homeostasis of organisms in which the amount of water in the organism needs to be controlled, via osmoregulation and behavior, such that the concentrations of electrolytes (salts in solution) in the various body fluids are kept within healthy ranges. the core principle of fluid balance is that the amount of water lost from the body must equal the amount of water taken in.