If you think you need to get on the floor to work your abs, I have another way. The majority of the abdominal exercises in the fitness world require you to lie on the floor, mainly on your back. But this can be a problem for people who have back injuries or someone who has a problem getting up and down from the laying position.
Sculpting your abs while standing offers plenty of bonus benefits—you'll engage more muscles at once, improve your postural support, and burn more calories than most traditional floor exercises. 
One of the biggest benefit of standing ab exercises is a lower risk of injury. Most people have a hard time doing Ab moves correctly. The basic crunch, for example, requires you to lift your neck and shoulders up off the ground. Unfortunately the majority of people do it wrong. They hold on to their neck and pull it up to get themselves off the ground. This will strain your neck. During standing moves, we eliminate many errors. It is much easier to control your neck and shoulders in a standing ab move then it is on the floor.
Standing Bicycle: Stand with feet together, knees slightly bent, hands behind head, and left heel lifted. Brace abs in tight and lift left knee up as right shoulder rotates towards knee (try to touch). Lower back to start. Do 20 reps, and then repeat on opposite side.
Standing cross crunch: Stand with your feet shoulder-width apart and hold a dumbbell in one hand. Extend the arm with your dumbbell over head and put your other hand on your hip for balance. Now lower the arm that was in the air as you simultaneously bring the opposite knee up across the body so that your elbow and your knee meet. Hold this position for about a second and repeat 20 times. Repeat the same move on the other side.
Leaning side crunch: Stand with feet together, knees slightly bent, arms extended overhead, palms pressed together. Lean torso to the right, stretching through left side. Next, brace abs in and slowly lean to the left as left leg extends out to the side, lifting leg with pointed toe. Do 20 reps, and then repeat on opposite side.
Repeater: Stand with your body on angle with one leg in the front with the knee slightly bent and the other leg in the back straight but not locking the knee. You are going to place both of your hands up above your head (your body should be on an angle, you shouldn't be standing up straight.) Bring the knee in the front up as you pull your arms down to put the knee. Pretend that you are holding a coconut in your hands and you are trying to break it using your knee. Perform this move a pretty fast pace. Time this one for 30 seconds for beginner and 1 minute for more of a challenge. Repeat the same move on the other side.
These are great for at home or when you are staying in hotel room or even a relatives house and remember only do the number of reps that you are comfortable with but make sure to record them so you can see your improvement. 
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