Careful, speed racer. There’s more to watch for while walking than potholes, snarling dogs, and traffic. How you go about putting those feet out in front of you could make or break your walking program, especially if you’re serious about getting fit. The more you walk, in fact, the more likely any irregularity in your walking form is going to sneak up from behind and “bite” you with an injury. But your style is fine, you say—the same as it’s been since childhood. Don’t let those be famous last words. “Most walkers aren’t aware when they’re walking inefficiently and making it harder on themselves,” says Cambridge, MA–based fitness walking and racewalking coach Ken Mattsson. “Many people jolt and jerk when they walk, for example,” Mattsson says. Or they swing their arms out too much. Such offenses might sound minor, but over time, their effects can mount up and put you down with a walking injury. But help is here. To keep you stepping in proper style, we asked Mattsson and other leading walking coaches to give us the rundown on the most common mistakes walkers make and advice on how to correct them. Don’t take another step until you’ve checked out these 5 common mistakes—and how to fix them.   Mistake 1: Your Posture Is Poor “Many walkers get hurt because they simply don’t walk erect,” says Bonnie Stein, a racewalking coach in Redington Shores, FL. The two most common posture problems? Walking bent over with the head down or its opposite: strolling leaning back. Either way, you set yourself up for injury, Stein says. Leaning too far forward or backward throws your body off balance, putting undue stress on your lower back, says Stein. The result? Strain and pain. How to Fix It: Don’t look down—or up. To straighten up, hold your head high, so your neck and the rest of your spine form a straight line. Don’t tuck your chin into your neck, and look well ahead of you. (Experts’ advice on the distance ranges from 10 to 30 feet ahead.) Also make sure your shoulders are relaxed, and your stomach is tucked. A way to check yourself, says Stein, is to take a big breath every 5 minutes, and exhale strongly. Notice how your shoulders drop? That’s how you want to carry yourself.Check your alignment. To avoid repeating old habits, mentally check the alignment of key body parts every so often, says Stein. As you step forward with your right foot, for example, check that your right ankle, knee, hip, and shoulder are in a stack. Do the same for your left foot. MORE: Your 10 Biggest Walking Pains, Solved Mistake 2: Your Style Is Sloppy Flapping arms, giant-size strides, stomping feet: These are among the more common “moving violations” walkers make, says Mattsson. These are the types of errors in walking form that can not only slow you down but also set you up for injuries such as shin splints. How to Fix It: Keep your arms to yourself. Yes, your arms should swing back and forth when you walk, but they shouldn’t flap willy-nilly from side to side or shoot up and take jabs at your chin. “If your arms are winging in and out, you’re sending energy sideways rather than propelling your body forward,” explains Mattsson. “Also, if you’re bringing your arms high up in front of you, you’re sending energy upward rather than forward.” Your body gets out of balance, and you slow yourself down. A better bet: Keep your arms bent 90 degrees, and place your elbows close to your sides, so they drive back, not outward, advises Stein. Envision a shelf extending out from your sternum, or breastbone, and keep your hands from shooting above it, she says.Take a measured step. “Many walkers overstride because they think they can move faster if they take a longer leap,” Stein says. Truth is, though, taking too long a stride actually slows you down, because a heel extended too far in front of your body doesn’t generate any forward propulsion. And when your foot is stretched out in front of you, it’s acting like a brake; you can’t easily roll from heel to toe, as you should, to generate the forward power. How can you determine just how long your stride should be? Stand up straight, and extend one foot a few inches in front of you with your heel not quite touching the ground. Then start to fall forward slowly; your extended heel will hit the ground and stop you. That’s where your front foot should be during your stride, says Stein. Don’t focus on where your back leg is during this test, warns Stein. Remember that when you’re actually walking, your back leg will be farther back.Listen to your footfall. Is it loud enough to wake the neighbors on a Saturday morning? If so, you need to lighten up. When you step forward, your heel should strike the ground gently before your foot rolls forward and allows you to push off from your toes. You’re stressing your feet and legs needlessly if you come down too hard. “Remember, too, that if you’re pounding your feet on the ground, you’re not channeling enough energy forward, and you’re stopping your momentum,” Mattsson says. MORE: 15 Teeny Tiny Changes To Lose Weight Faster Mistake 3: You’ve Got the Wrong Gear Too many walkers carry needless stuff—hand weights, for example—and forget to tote the important things, such as water, says Stein. Packing extras can keep you from your peak walking performance. How to Fix It:Lose the weights. Contrary to popular belief, walking with hand weights doesn’t necessarily make for a more intense workout than walking empty-handed, says Marilyn L. Bach, PhD, a walking coach in St. Paul, MN, and coauthor of ShapeWalking: Six Easy Steps to a Healthier Life. Some studies, in fact, show that walkers slow their pace when carrying hand weights and risk shoulder and forearm injuries in the process. The best and safest way to add weight to boost your calorie burn and the bone-building effects of walking is to carry a weighted backpack, or wear a weighted vest. Bach’s recommendation? Work out with weights at home or at your gym. Done properly, training with weights will strengthen your muscles, make your walks more efficient, and help protect you against injury, but it’s best to lift weights independent of your walking program.Walk with water. “Few walkers drink enough water,” says Stein, who pushes her students to tote a supply whenever they plan to walk for more than 15 minutes. Guzzle ½ to 1 cup of H2O at least every 30 minutes, she advises. If you’re hot, drink more often, every 15 to 20 minutes. Unburden your hands by carrying your supply in a fanny pack that has an insulated water-bottle holder, preferably one with a solid base, she adds. “If you get the kind with just two crisscrossed straps to rest the bottle on, water will drip from the bottle onto your legs,” she says. Mistake 4: You Go Out Fast and Stop Suddenly Every walker is guilty of this blooper from time to time: the “I’m in too much of a hurry for a warmup or cooldown” syndrome. Careful. Sure, you can save time by diving right in—and out—of a workout, but you’ll pay sooner or later, somehow, especially if you make it a habit. Risk of injury aside, starting your walk suddenly at a breakneck pace will only increase the odds that you’ll wear out before you’ve covered much ground. It’ll also leave you sore and vulnerable to a whole host of injuries, says Jake Jacobson, a Levittown, NY–based racewalking and walking coach and the author of the book Healthwalk to Fitness. Skipping the all-important cooldown and stretching phase also can have drawbacks. It can leave you feeling temporarily faint, for one thing, and rob you of invaluable flexibility, for another. How to Fix It:Start slowly. Spend the first 5 minutes of your walk in stroll mode, advises Jacobson. This will increase blood flow to your leg muscles and warm them up, which is important for protection from injuries.Accelerate gradually. Once you’re warmed up, increase your pace gradually. Accelerate until you’re walking as fast as you would if you were on your way to an appointment, suggests Bach. For a more vigorous workout, gradually increase your speed until you’re walking as fast as you would if you were 5 minutes late for that appointment. To push harder yet, imagine you’re 10 minutes late.Cool it. Spend the last 5 to 10 minutes (or final few blocks) of your walk in stroll mode again, for a generous cooldown. “Any time you’ve walked vigorously enough to elevate your heart rate, it’s essential that you let your body cool down gradually,” Stein says. If you stop suddenly, all the extra blood that’s being pumped into your leg muscles can pool there, leaving you feeling dizzy and overheated.Stretch it out. Follow your cooldown with basic stretches so your muscles don’t get stiff and tight, adds Bach. Be sure to stretch your hips, your hamstrings, your calves, and your shins. Here are some good strengthening and stretching exercises to add to your basic repertoire of hip, hamstring, calf, and shin stretches: Hip Extender Stand with your back straight, arms at your sides, and your feet shoulder-width apart. Step forward with your right foot, bending your right knee so that your right heel hits the ground. Press your right leg gently toward the ground, and flex your right foot upward. (You should feel a stretch along the back of your right thigh.) Hold for 10 seconds, release, and stretch again, holding for 30 seconds. Repeat with the left leg. Tiptoe Raise This move stretches your calves. Standing straight, arms at your sides, raise your toes off the floor, hold for 2 beats, then slowly lower them. Repeat. MORE: 11 Highly Effective Solutions For Sciatica Toe Stretch While sitting on the ground, cross your legs so that your left ankle rests on your right knee. Hold your left ankle and heel with one hand, and hold the top of your left foot and toes with the other. Slowly pull your toes toward the sole of your foot. Hold for 30 seconds, then relax. Now work your right foot. Back Relaxer Lie on your stomach with your arms at your sides and palms facing up. Arch your back, slowly lifting your chest off the floor to a count of 2 beats. Hold for 2 beats. Then slowly lower your chest to the floor to a count of 2 beats. Over time, do the exercise more and more slowly until each step takes 4 beats. Mistake 5: Your Route’s a Bore You’d think it’d be a no-brainer to keep walks fun and challenging, but many of us let ourselves fall into ruts, say the experts. “So many walkers just don’t bother planning their routes in order to keep them interesting,” says Bach. “They tread the same roads or paths every day, and then they’re surprised when they get bored.” How to Fix It:Change the scenery. If you’ve been walking the same loop around the local high school, spin through your area’s botanical gardens instead, suggests Bach. Ask whether your city hall or chamber of commerce publishes a walking tour of your area. (Most cities, even small ones, do.)Head for the hills. Walking up and down moderately steep hills (a slope of about 4 to 8% will do) affords a substantially more strenuous workout than walking on flat terrain. And there’s nothing like challenge for giving monotony a run for its money. “You’ll stay committed if you set goals for yourself and keep progressing,” says Bach.Try intervals. For 30 seconds, walk as fast as you can. Then, for the next 90 seconds, slow down to your usual pace. Repeat this pattern a few times, and you’ve successfully walked intervals. Again, the more you challenge yourself, the more interested you’ll stay.Walk longer. An occasional extended walk (more than 4 miles) adds interest and challenge to a humdrum routine. Just remember to add a manageable distance when you lengthen your jaunts. (Mattsson suggests increasing your distance no more than 5% a week.) Your body needs time to adjust to longer treks. And limit long walks to once a week: Too much too often will leave you weary as well as injury-prone.Take breaks. “If you keep pushing yourself every day, you’ll get used to it, but you’ll always feel somewhat worn out,” says Mattsson. Give yourself a day or two off from walking every week, particularly if you’re adding a long weekend hike. You’ll feel rested and ready to hit the trails blazing.