Posture refers to how we hold ourselves up.
You can have good posture (standing or sitting straight) or poor posture (slouching and rounded shoulders).
It's not only important for how you look but also how you function.
Good posture helps you breathe better, move more efficiently, and have more endurance.
If you get into bad habits with posture now it can cause problems with the muscles, joints and bones of your spine in the long term.
Many activities can affect your posture like carrying a heavy back pack (or wearing a bag over one shoulder only), sitting slumped, working at a desk for long periods without taking breaks, poor lifting, and being inactive or unfit.
A great way to remember good posture is to imagine a balloon attached to the top of your head pulling you gently upwards (but keeping your feet flat on the ground).
Also, be sure to practice the Straighten Up exercises daily... it's fitness fun for everyone!
It's important to wear both straps of your backpack to spread the weight. It should weigh no more than 10% of your body weight (5% for children under 10 years).
You can tell a backpack is too heavy if you have to lean forward or have rounded shoulders when wearing it.