1. It lowers your confidence.
The proper posture makes your body release testosterone, the hormone associated with great confidence. It even helps you think and feel powerful. So if you're slouched or hunched, you're not helping yourself feel good and strong.
2. It doesn't make you look classy.
Not that it's bad if you don't look sophisticated. But if you have to look the part but you actually don't? People will be more inclined to have a very "meh" impression of you—and you wouldn't want that especially when you can build your network for whatever future endeavor you might have.
3. It makes you less productive.
Not only are you making yourself prone to back aches when you're not straightening your back. You're also making yourself more prone to migraines, have troubles focusing, and not have energy. Your vital organs are in your core, and when you're slouching, those organs get compressed. That hinders their optimal functioning.
4. It keeps your stress levels high.
When your body is caved in, your breaths become short and strained, so your heart becomes worked up from trying to provide blood for oxygen transport to different parts of your system. That induces stress. So straighten your back to expand your chest so you can take deep breaths. It'll also decrease the production of cortisol, the stress hormone.
5. It makes you feel down.
People with bad posture have been observed to be more negative. They say more negative things than positive, and they express negative emotions more as well. But people who straighten themselves up were found to not drop into negativity easily. Research has found that just as exercise boosts our mood, straightening our posture does the same since it keeps our energy up.
6. It makes you look heavy.
This isn't good when you want to look slim. Slouching will make your internal organs go out, creating bulges on your body. Totally applicable when you're sitting down all day—so yes, even the way you're sitting can make you look fat.
7. It disrupts your digestion.
Your intenstines get folded up more, and that slows down digestion. Keep your back straight and stand up or take a walk right after you eat.
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