It's important to note that all bodies are different and that we each assume our own "natural posture," which varies from person to person. Still, there are some rough guidelines that everyone can follow.

"Your feet should be pointed straight forward and hip width apart. The arches of your feet should be sitting off of the ground, and your kneecaps should be pointing slightly outward. This means your hip external rotators are actively maintaining lower extremity posture," notes Joyce. "Your glutes should be holding tension to ensure your hips do not tilt forward and that your lumbar spine is not in an extended position."

In addition, he notes that your core should be holding tension, which helps further brace your lumbar spine and anchors down your ribs. This helps build a strong foundation for your torso to sit on.

Moving up your body, Joyce says your shoulder blades should be relaxed down (away from your ears) and slightly inward (toward your spine). Lastly, your chin should be slightly tucked with eyes facing forward with your line of sight parallel to the ground.

"In a perfect world, from a lateral view you would be able to draw a vertical line through the ear, dissecting the shoulder joint, through the lumbar spine, slightly anterior to the midline of the knee, and just anterior to the ankle joint," he says.

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If you work an office job or if you're in school, you probably find yourself sitting quite a bit. When doing so, "your head should be over your shoulders with your shoulders over your pelvis," notes Dr. Rahul Shah, a board-certified orthopedic spine and neck surgeon. Yalamanchi adds that it's also best to maintain a 90-degree angle at the hips and knees, and to keep your feet flat on the floor.

Finally, Dr. Shah says, "While working at a desk, it is important to switch up your position from time to time so that you don't fatigue your back or shoulders." Try standing up and walking around once an hour. Bonus points for doing some stretches! This will also give your eyes a break from the screen!

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Sleeping is another one of those things that varies from person to person, but ultimately your goal should be to feel supported at key places — including your neck and spine — throughout the night.

"While sleeping, the use of a pillow can make a huge contribution to keeping your spine neutral and your body happy," notes Joyce. "If you sleep on your sides, a pillow between the legs will keep your top leg from pulling the lumbar spine out of neutrality. Also hugging a large pillow can help stop the top shoulder from falling forward and pulling the neck with it. If you sleep on your back, a pillow underneath the knees with help to keep tight hip flexors from pulling your lumbar spine into extension."

Also important: your pillow height! Too big or too small and your neck will fall out of alignment and put you at risk to wake up with stiffness. Ultimately, it is important that your pillow allows your cervical spine to stay parallel with the ground.

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By understanding what bad posture looks like — and what good posture looks like — you're really already halfway there! Pats on your (upright) back for getting this far. In the next few slides, we're outlining some easy and concrete ways you can improve your posture starting as soon as today.

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"You must reverse the positions that you spend most of your time in," says Joyce. "Many people find it useful to put on a recurring timer that reminds them to get up and move on a regular basis."

For example, if you sit at a desk with your hips flexed and shoulders and arms forward, then take time each day to extend the hips and get your chest opened up with your arms out to the side.

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