Fitness walking — taking longer, faster-paced walks — is a key element of many exercise programs. If offers loads of health benefits, including preventing and managing conditions like heart disease, high blood pressure and type-2 diabetes; strengthening bones and muscles; and improving mood, balance and coordination, according to the Mayo Clinic.

Seems like an easy fitness choice. But are you doing it right?

It may sound strange, but many people walk incorrectly — and they don't even know it.

If you like to walk, but have found that you experience soreness in your joints (not just tired muscles), or really sore feet, ankles, knees, hips or shoulders, or you experience pain when you walk, it's time to see a doctor. Chances are something's off — maybe from an old injury, but maybe the way you're walking is resulting in pain and discomfort. You should feel tired after a brisk walk, but you shouldn't feel pain.

Let's go through what you might be doing wrong, starting with this video of physical therapist Dr. Justin Lin, who walks through some of the potential pitfalls.

Foot placement

You should be rolling your foot from heel-to-toe, which will result in a smooth leg motion. When you're in mid-stride, you should be moving forward because you're pushing off the ball of the rear foot, not because you're pulling forward with your front leg or foot. At least one of your feet should be on the ground at all times. If you hear a slapping sound when you walk, you're landing too abruptly; it should be more of a rocking motion than an up-and-down one.

Keep your head up

It's important to keep your head upright; you shouldn't be looking down at the ground as you walk. Yes, you do need to see where you're going to avoid on-the-ground hazards. So how do you do both? If you're used to looking down at the ground the entire time you walk, you might be confused about this one, but it's a small skill that just takes a little practice. And you can do it even over complex terrain.

Take a few walks during which you practice scanning the trail or sidewalk in front of you as you move forward. At first it will feel strange if you're used to staring at your feet, but you'll soon realize that unless it's a tricky section of terrain or there's a real obstacle in your way, for the most part, you can just glance down briefly at the edge of the sidewalk or the branches across a trail. You'll be surprised at how little you need to look down once you get the hang of it.

Don't slouch

Two young men take a walk in a park. Walking with a friend can be a good way for each of you to remind the other about posture and breathing. (Photo: Dragon Images/Shutterstock)

As much as you can manage, keep your back straight and your stomach muscles engaged (this means that you can feel them a bit tighter than if you are sitting, but it's not like you're squeezing them so they are really hard). Michele Stanten, a certified group fitness instructor told Real Simple: "Your spine should be straight, with your ears over shoulders, shoulders over hips, and hips over knees." If you are used to slouching a lot, this can be the most challenging part of a new walking routine, but it's important. You can practice strengthening your core with some basic exercises like these.

Relax

If you walk with your neck and shoulders up around your ears, your butt tight, or keeping your back stiff, you'll get tired quickly and probably won't be breathing as well. As you walk, your upper body and torso should be mostly relaxed, your shoulders low, arms and legs swinging, not forced into a lock-step. Breathe deeply, but don't force it. Shallow breathing will make you feel more anxious though, so the more deep breaths you can get in, the more relaxed you will feel.

The best part about walking is that you can do it almost anywhere, as long as you're dressed appropriately. So put on your most comfy shoes, keep the guidelines above in mind, and just walk.

Starre Vartan ( @ecochickie ) covers conscious consumption, health and science as she travels the world exploring new cultures and ideas.