Ah, sitting. That thing that we do seemingly all the time — so we should be pretty good at it.

Except that, if our backs are any indication, we don't sit very well at all.

Luckily for our backs — and the rest of our bodies, really — adjusting how we sit isn't all that difficult. All it takes it a little bit of practice.

Sit better

To a certain extent, our chairs are to blame. Speaking to NPR, Galen Cranz, who studies chair design at the University of California, Berkeley, explains that prior to the 20 century, people in the West sat on firm and flat chairs that were constructed with human beings in mind. Once designers got their hands on new materials, like plastic and steel, chairs started getting softer and bigger.

The result? A bunch of places to sit that are bad for our backs.

"It's shocking how poorly designed they are for our bodies," Cranz said.

According to Jean Couch, a sitting expert who has taught people better sitting and balance at the Balance Center for more than 20 years, chairs these days are just too deep and too soft. When chairs are the former, our legs can't touch the floor without slouching, and when they're the latter, we bend into a C-shape. Neither of these options are good for our spines.

No need to get new chairs, however. Couch has a few easy ways for you to sit better on just about any chair.

1. Be at the edge of your seat. Normally this is just when you're anxious, but sitting on the edge of the chair is normally just a good idea anyway. Find a chair with a nice wooden frame, and use this for support, ignoring the back rest. This helps to keep you from curling into that C-shape.

The key, however, is positioning your legs. Put your knees below your hip socket instead of aligning your torso and legs at a 90-degree angle. "Something like 120 degrees," Couch tells NPR, is better since you'll be less likely to slump.

Jen Sherer, who worked with Couch for nine years, has started her own sitting and back clinic called Spinefulness in Palo Alto, California. The video below provides a quick primer on how to find that sweet spot for your body and your chair.

2. Too soft and no perch? Build one. If the chair doesn't offer the support for perching, you can make a perch for yourself. This perch can be just about anything: A jacket, sweater, pillow, even a wallet. Couch favors an incline pillow of pretty dense foam.

Place whatever the object is a few inches from the chair's front edge and then sit yourself along the front of the perch you've made. The perch will tilt your pelvis forward, and this will give your sitting bones, aka your ischial tuberosity bones, something firm to sit on, which in turn helps prevent you from getting into that C-shape. The perch will also raise your hips a bit, making it easier for your legs to find that 120-degree space of comfort.

3. Applying all this to your car ride. You can't sit at the edge of your car seat, since that's not particularly safe. These seats are, like airplane seats, are also shaped like Cs, so they encourage slumping. Fixing this is relatively easy, however. Take a firm pillow, or that handy jacket, and place it around your mid-back. This, again, pushes you forward a little bit so you have an I-shape instead of a C-shape.

How to sit in a chair so your back is happy
Get better at sitting with a couple of easy tricks from the experts, and some knowledge about how chairs have changed over the years.