Do yourself a favor and release the tension from your shoulders. You should also unclench your jaw, and release your tongue from the roof of your mouth.
We hold a lot of our stress physically, and there’s a feedback loop between how our bodies feel, and the mental state we’re in. When your body is tense, you feel tense; when your body is relaxed, you feel relaxed.
We all experience tension at times, and unless you pay close attention, that feedback loop is ripe to spiral out of control.
Floating allows your body to relax completely and starts shifting your mind to feel the same. It’s just one of the reasons the world feels a little calmer after a float.