Half a century ago, people knew the consequences of bad posture — but they seemed to focus more on decorum than health risks. After all, slumping wasn't the proper thing to do, so mid-century gurus offered what they thought were good posture exercises at the time: Balancing a book on your head to train your back into better alignment.

Of course, we now know that posture isn't just about looks, nor can it be solved by books. Slouching leads to back pain, breathing challenges, digestive issues and more, according to the National Institutes of Health. Unchecked, it can snowball into an even bigger problem, warranting physical therapy or even surgery.

So what's there to do? While our modern-day desk jobs and TV bingeing can make bad posture worse, many types of active exercises can help reverse the damage, no books required. Try these good posture tips and poses to find what works for you:

1. Yoga and Tai Chi

Eastern-inspired exercises like yoga and tai chi get a lot of hype for good reason: They lift your mood, boost your flexibility and do wonders for your posture. A variety of different approaches for yoga in particular ensures that anyone can find the right practice for them, from cardio-pumping flow yoga to more meditative versions that focus on deep breathing and mindful poses. Get started with these easy poses from the Cleveland Clinic.

2. Wall Stands

Want to know what good posture feels like? A wall stand is a great place to start. Stand with your back against the wall, and align your whole body (from head to feet) to it. Slightly push your pelvic area forward so that your lower back can rest entirely against the wall. Make note of how that feels, and work to apply that posture anytime you're standing or sitting up, from work to the car to the couch. See this illustration for a good visual guide.

3. Flat Back Knee Pulls

Lie down on your back with your feet together. Lift your right knee to your core, and hold it there for 5 to 10 seconds. Alternate your knees until you've done both knees for five times each. See this photo to make sure you're doing it right.

4. Back Squeeze

Best done in a chair, this exercise is great for opening up your chest and stretching the back — and you can do it in any place where you can sit up straight — even your couch. To do it, squeeze the shoulder blades back, almost as if you're trying to pinch a pen in place in the center of your back. Hold each squeeze for five seconds, and repeat up to five times daily. See this photo from the Mayo Clinic.

5. Seated Back Twist

Try opening up your chest and stretching your hips with this feel-good pose. Sit on the floor with your left knee raised and right leg flat on the ground. Put your left foot over your right knee, and place your right elbow on your left knee. Slowly twist your shoulders toward the left side and look left. Hold for 30 seconds, and then do the other side. See this photo.

6. Abdominal Rest

Maybe the easiest one of all, this exercise takes little to no effort beyond laying down, stretched out, on your stomach. Doing so can help stretch the muscles along your spine. You likely don't need a visual guide for this one, but if you do, Consumer Reports has you covered.

7. Forearm Plank

Here's one of many good posture tips: Improving core strength is one of the best ways to improve your posture, and planks offer ample opportunities to do just that. Get down on the floor as if you're about to do a push up, with your hands under your shoulders and your legs aligned with your back. Still keeping your back and legs aligned (like a table) lower your forearms to the ground and stay there as long as you can — ideally, about 60 seconds. Watch it done with this video.

8. Quad Stretch

You might think the age-old standing quad stretch is just good for your quadriceps, but it does more than that. By forcing your body to stand upright on one leg, it's an exercise in good balance too, which can support overall back health, open up your chest and shoulders, leading to better posture. You've probably seen it done a million times, but just in case, this photo is a classic example.

9. Cat Cow Stretch

Often seen in yoga sequences, this stretch can help you get your back, shoulders and chest in posture-friendly places. To start, get on your hands and knees in a "neutral spine" position, that is — a flat back. Slowly lower your head and arch your back into a "cat" pose, and then tilt your head up as you lower your back into a "cow" pose. See this photo for a guide.

10. Pelvic Tilts

As a core booster, this exercise can help build the strength your back needs to stand up straight. Lie down with your back against the floor and knees raised. Use your abs to drop your back closer to the floor and tilt your pelvic area up. Hold the pose for 10 seconds, and then do it again. Refer to this illustration from the Mayo Clinic.

Luckily, gone are the days of book balancing for the sake of good posture. But not-so-luckily, modern-day job and home life can disrupt even the best intentions and efforts to stand up straight. Try these good posture exercises the next time you feel yourself slumping — and get ready to feel better, inside and out, when you do.