A strong core helps with posture, balance and stability, and can prevent and reduce back pain. To effectively strengthen your core you need to work the low back, glutes, pelvic floor and the abdominals, which are the primary muscle group of the core. This makes ab exercises an important part of any fitness routine. While crunches are a common ab exercise that are often the go-to, they can be tricky to do correctly. Common form mistakes, like pulling on the neck or using momentum, can cause pain and injury. Luckily, if they cause you trouble, there's no shortage of exercises that accomplish the same goal. Even if you've mastered crunches, a well-rounded ab routine includes exercises that work the core from different angles, so it's smart to include some of these other moves that target and strengthen the core, too. Plus, they have the bonus of not putting stress on the neck or low back. For more ab workouts — plus meal plans, fitness challenges, walking podcasts and inspiration — download the Start TODAY app! How often should I train abs? While large muscles in our upper and lower body need at least one day of rest in between training to recover, the smaller muscles of the core can be worked every day. String together 5-7 of these exercises for a quick 5-minute core routine you can easily fit into your schedule. When you have extra time, turn it into a circuit workout by repeating 5-7 exercises for 3 rounds total with a short rest in between. The best at-home ab exercises Pelvic tilt A pelvic tilt is always a great way to begin a set of ab exercises in order to wake up the core and practice engaging the proper muscles. Lie on your back, bend your knees and place your feet flat on the floor. Make sure your feet are hip-width apart and your arms are reaching down towards your feet. Then take a deep breath, and feel your lower back arch slightly off of the ground. Then exhale as you tilt your pelvis forward and press your low back into the ground. Pull in the naval toward your spine as if you’re zipping into a tight pair of pants. Release and repeat 10-12 times. Plank Start on your hands and knees, and line up your shoulders over your wrists, making sure the wrists are parallel with the front of the mat. Next, walk your knees back a few inches and pull your navel in toward your spine. Tuck your toes under as you lift your legs up off the ground. Squeeze your quads and reach your heels toward the back of the room. Make sure your shoulders are over your wrists, and that you’re looking a few inches in front of your fingers to keep your head and neck elongated. Hold for 30 seconds, working your way up to a minute. Side plank Start in a modified plank position on your forearms. Hug the legs together and bring the left foot to touch the right. Next, slowly turn to the right with control, and move the right foot onto its right outer edge, stacking the left foot on top. Pull the right hip up and press down through your right hand, keeping it directly underneath your right shoulder, and slowly bring the left hand onto your left hip. Extend the left arm straight up to the ceiling, and hold the position for 30-45 seconds before coming through plank position again and switching sides. Mountain climbers Begin in plank position, keeping your back straight, your hips low and your core engaged. Bring your right knee under your chest toward your right elbow. Return your right leg back to plank position; bring your left leg under your chest toward your left elbow. Repeat, alternating your legs and keeping a steady pace. Remember to breathe and concentrate on engaging your abs, glutes and hamstrings. Perform for 30 seconds. Flutter kicks Lie on your back with your legs straight up toward the ceiling. Let your arms rest down at your sides. You can also place your hands under your butt for increased stabilization. Squeeze your core and lower both of your legs 6-12 inches down to about a 45-degree angle. Lift one leg up as your lower the other toward the floor. Switch legs. Continue to alternate, moving your legs in a flutter motion. Repeat for about 15 repetitions, and make sure not to speed up as you go. Reverse crunches With your knees bent, squeeze your abs and raise your legs so that your knees are hovering over your hips at a 90-degree angle. Keep your calves parallel to the mat so that your legs are in a table-top position. Engage your core as you lift your hips and knees toward your chest. Think of tilting your pelvis forward. Keep your entire upper body on the ground. Make sure that only the lowest part of your back comes off the ground; nothing higher. Keep the legs in a 90-degree angle throughout the entire movement as you come back down, through table top, and tap the feet on the ground. Repeat the steps, remembering to breathe slowly while squeezing your abdominals. Perform 10-15 reps. Russian twist Sit on the ground with your knees bent and feet either hovering above the floor or resting on the ground. Tilt your upper body backward to a 45-degree angle (this will feel like you are at the top position of a situp). Hold a dumbbell in both hands, squeeze your shoulder blades together and pull your shoulders away from your ears. Keeping the dumbbell in front of your chest, twist your torso to the right, tapping the dumbbell on the floor, then move back through center and twist to the left, tapping the dumbbell on the floor. Repeat 5 times on each side. For a modification, perform the move without a dumbbell. V-sit Seated on a mat, engage your core muscles and gently lean back a couple of inches. Slowly lift your legs up in the air so that are in a table-top position. Reach your arms straight out in front of you so that they are parallel with the mat. Keeping your core engaged, extend the legs straight up to a 45-degree angle, forming a “V” shape with your body. If you feel balanced here, attempt reaching your arms up toward the ceiling. You always have the option to leave them straight out in front of you. Hold this position for 10 seconds, working your way up to 20 and then 30. Keep the shoulders relaxed, abs pulled in and the inner thighs squeezing together. Release your legs and arms down to the starting position. Bicycle crunch Lie on your back with your knees bent and your feet flat on the ground as wide as your hips. With your hands behind your head and your elbows bent out to the sides, use your abs to lift your left shoulder blade off the ground. At the same time, bring your right knee to meet your left elbow. When your right knee is bent, straighten your left leg and reach it out in front of you at a 45-degree angle. Perform on the opposite side, bringing your left knee to your right elbow, straightening the right leg. Continue alternating legs and squeeze your core. Brush your inner thighs together as you switch sides to ensure you’re hugging your legs in toward the midline of your body. Perform 10 reps on each side for 20 total. Toe taps Lie down on your back. Imagine you’re sitting in a chair, with your knees at a 90-degree angle; your shins should form a parallel line to the ground. For best results, point your toes. Keeping your right leg still, tap your left toe on the ground, maintaining a 90-degree angle at the knee. Return it back to table-top position and then tap the ground with the right toe. Continue alternating legs for 30 seconds. Heisman Start standing tall with feet hips-width apart. Shift your weight into your left foot and bring your right knee toward your chest. Jump on to your right foot, bringing the left knee toward the chest. Balance for a moment before jumping back to the left foot, bringing the right knee toward the chest. Engage the abs to maintain proper posture and balance. Pump your arms and continue alternating for 30 seconds. Inchworms Start standing tall with your feet hips-width apart. Reach your hands down toward the ground, keeping your legs as straight as your flexibility allows. (You can bend the knees as much as you need to get your palms to the ground.) Keep the toes planted and engage the core to keep the hips stable as you walk your hands forward into a full plank position. Pause for a beat before walking your hands back toward your feet and coming up to stand. Repeat for 10-12 reps or 30 seconds. Situps Lie on your back and bend your knees so that your heels are on the floor. Place your hands behind your head and bend your elbows out to the sides. Squeeze your abs as you curl up with your head, neck and chest. Lift until you’re sitting up as high as you can without rounding your elbows in, and exhale as you lift. The goal is to sit all the way up so that your chest almost reaches your knees, with a straight back. Lower your body back towards the ground slowly while inhaling. Repeat for 10-15 reps. Plank dips Start in a modified plank position on your forearms. Hug the legs together and bring the left foot to touch the right. Slowly turn to the right with control, and move the right foot onto its right outer edge, stacking the left foot on top. Pull the right hip up and press down through your right hand, keeping it directly underneath your right shoulder, and slowly bring the left hand onto your left hip. For a easier modification, stagger the feet heel to toe. In a controlled motion, let your hips sink a few inches toward the ground. Then squeeze your obliques to pull your torso back into alignment. Repeat for 10-12 reps or 30 seconds and then switch sides. Cobra This one is a great stretch for the abs after a core workout! Place your hands alongside your chest and push an imaginary marble forward with your nose to lift up your head, neck and chest. Press down firmly through your hands and hug your elbows in towards your sides. Pull your navel in toward your spine and press your thighs down into the ground. Bring the shoulders back and lift the chin up. Take a deep breath in, and then rest. Repeat 5 times holding for a long period at the top if it feels good for your body.