Here's the great thing about ab exercises: You can add highly-targeted moves that sculpt your obliques, make your abdominals pop, and build a strong foundation of core strength to pretty much every single workout.
To do that, you can mix abs-focused exercises with explosive moves in a HIIT routine to build muscle and torch fat simultaneously. Or, you can hit your abs at the end of a strength-training routine. Doing both is actually optimal. Switching things up keeps your body guessing and muscles growing.
What you shouldn't do is train your six-pack muscles alone—and neglect the rest of your body. "The biggest mistake people make when they're trying to get toned and muscular abs is focusing on just ab exercises and crunches day after day," says Akin Akman, C.S.C.S., group fitness instructor and personal trainer.
In other words, you can't spot train. Perhaps more importantly, you can't work off a crappy diet. In fact, abs exercises are practically useless if you aren't watching what you eat.
"Getting toned abs is the same as getting toned anywhere else in your body—focus on clean eating and crosstraining with both cardio and strength moves to create the higher metabolic rate that will lean your body as a whole," Akman adds.
Prescription: The reps Akman recommends for each exercise that follows are meant for an ab-specific workout that will take you approximately 30 minutes to complete if you do 2-3 sets. Take as little rest as possible between reps, and give yourself a few minutes between sets. "Don't rest too long, though, because you want to keep your heart rate up and your muscles engaged," Akman says. You can also just pick and choose a few of these moves to add to the end of your strength training workout or incorporate into a HIIT routine.
If you're just using your bodyweight, keep the reps and sets high. If you're incorporating heavy weight with some of the moves, do lower reps with more sets. Modify the workout according to the intensity and duration you're looking for.
1. Hollow Rocks
How to do it: Lie on the floor with your legs straight out in front of you and arms extended overhead. Maintain contact between your lower back and the ground as you raise your upper body off the floor, using your core. Keep your arms straight (behind your head) and your toes pointed away from you. Engage your abs as you hollow your belly and slightly round your lower back. Lift your legs off the floor as you raise your shoulders, pulling you back toward the ground. "Start rocking back and forth while keeping your body tight and maintaining the hollow body form," Akman says.
Expert tip: "Make sure your back stays rounded with your pelvis tucked under, and don’t raise your legs up more than a foot off the ground as you rock back and forth," Akman adds. Use your lower abs to get that momentum going, not your legs.
2. Russian Twists
How to do it: Sit on the ground with your knees bent at 90 degrees and your torso at a 45-degree angle from the ground. Keeping your back straight and your hands at your chest, explosively twist your torso as far as you can to the left, trying to touch your left elbow to the ground. Reverse the motion, and explosively twist to your right, trying to touch your right elbow to the ground. This is one rep.
Expert tip: Focus on form. Because the movement is quick, take extra care that your spine is straight instead of rounded to avoid added stress on your lower back. "For a more advanced and tougher workout, hold a medicine ball, dumbbell, or weighted plate at your chest and keep your legs straight out in front of you, off the ground," Akman suggests.
How to do it: Lie on the floor in a hollow body position (like slide 1) so your upper body is off the floor, your arms are extended overhead (at your ears), and your legs are straight out in front of you. With your feet together and toes pointed, raise both legs up, keeping them completely straight, while raising your upper body off the ground. Touch your hands to your toes.
Expert tip: "Squeeze and engage your lower abdominal muscles to reach for your toes without bending your knees, and then lower yourself back into hollow rock position," Akman says.
How to do it: Start standing tall with feet your together. Hinge at your hips and reach your hands to the floor. Begin walking your hands out until your body is parallel to the ground and you're at the top of a pushup. Keep your hands underneath your shoulders as you slowly walk your feet up toward your hands. Be mindful of your flexibility; try to get as close to your hands as you comfortably can. Walk your feet back out into plank position without bending your knees. This is one rep.
Expert tip: "Keep your legs and back straight while squeezing your abdominals to walk your feet up to your hands," Akman says.
Duration: 1 minute
5. Full Weighted Situp
How to do it: Lie down with your back flat on the floor and legs straight out. "Holding a weight at your chest, slowly bring your upper body up for 4 seconds and come into a sitting position so that your torso is perpendicular to your legs," Akman says. Slowly lower your upper body, for another 4-second count, back down into the starting position. Repeat.
Expert tip: Keep your back completely flat and your legs and feet glued to the ground, Akman says. At no point should you bend your knees.
Duration: 1 minute
6. Extended Arm Plank
How to do it: Start in a pushup position. Slowly walk your hands out as far out in front of you as you can manage; keep your hands and fingers pointing forward. Pause, maintaining straight arms and back, and hold for 10 seconds. Walk your hands back into a regular plank position.
Expert tip: Make sure your butt is low to the ground, not sticking up in the air, when you're in the extended phase of the plank, Akman says.
7. Oblique V-Ups
How to do it: Starting on either your left or right side, lie sideways on the ground on your hip with your legs angled 30 degrees from your waist. With a dumbbell in both hands—either at your chest or above your head with your arms at your ears—lift your legs and torso toward each other. Keep your legs straight as you contract your oblique muscles to complete the V-up, then come back down to the starting position.
Expert tip: Keep your back rounded and your head in neutral position to avoid uncessary strain, Akman says.
8. Towel Knee Tucks
How to do it: Start in a pushup position with a towel under your feet on a smooth surface (wood or tile floor). Keeping your core and glutes tight and your hands positioned under your shoulders, draw your feet in toward your torso in a smooth, explosive movement. Bring your feet as far in toward your hands as possible so your knees are bent underneath your torso, grazing your elbows. Slide your feet back out into a pushup position. This is one rep.
How to do it: Start in pushup position with your hips centered and hands underneath your shoulders. Bring your left foot diagonally across to your right hand, then alternate by bringing your right foot to your left hand. This is one rep.
Expert tip: "Make sure to keep your butt down and squeeze your glutes and obliques," Akman says. Your core is the main mover here.
10. Bicycle V-Ups
How to do it: Lie down in a hollow body position with your legs straight out on the ground and your arms extended behind you. In one swift movement, bring your left leg and upper body off the ground into a 45 degree angle. Touch your right hand to your left foot while keeping this leg straight and as close to your torso as you can manage. Hold your left arm out to the side for balance. Return to the starting position and repeat the movement on the other side, so your right leg is straight up in the air and your left hand makes contact with your right foot.
Expert tip: "Engage your core and obliques to bring your legs up as high as possible without bending your knees," Akman says.