now i know that a lot of people sit there and say that being sedentary causes you to become obese. but i've been sedentary and i am (currently) almost underweight. i've also been laying down a lot the past three months, and cannot handle standing or walking due to the fact my heart rate goes through the roof (120 BPM's). i have not been diagnosed with P.O.T.S. but am having a hard time just plain walking (because my body exhibits symptoms i used to only experience when running) as well as i'm out of breath when walking. i also notice that when i am sitting my heart rate is around 100 BPM's is this something to be concerned too much about. my mom says that my heart is normal (because she's listned to it and is currently in nursing school) but i have all these weird feelings and don't know what to think.