While bodyweight moves work your entire body, some of them really target your core. If you are looking to tighten your ab muscles and strengthen your core, definitely add these moves to your workout routine.
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Coach Mag
Reverse Crunch
This might sound like a simple crunch, but you are going in reverse, and it is much more complicated. The good news is that it works your lower abdominals, which are notoriously difficult to engage. If you have a low belly pouch you are trying to minimize and tone, this is an excellent bodyweight exercise to do. The reverse crunch starts with you lying on your back with your legs out in front of you. Put your hands behind your head to support your neck, then cross your ankles. Lift your feet up and toward the ceiling, then back down. When you lift up, you want to try to get your buttocks off the ground. You can start this by bending your legs, but eventually you should be able
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Prescription Fitness
Different Types of Planks
All the different planks you do will work out your abs in a minimal amount of time. Crunches can only get you so far, plus planks work other areas of your body as well. Start small with the elbow and standard planks, holding it for as long as you can. You can then start adding more planks, like side planks, shoulder taps, and pulling your knees in to your chest one by one. The great thing about planks is that they engage your abs and have modifications to make them more difficult.
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Leading Asian Man
Leg Lift
This is similar to the reverse crunch, except you want to keep your legs straight, and don’t need to lift them all the way up. Instead, you are going to reach your legs out while laying on your back, lift your legs about 6 inches, then lower back down. Continue doing this as many times as you can. If you have a bad lower back, this might not be the best ab move for you.
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Abs Workout For Men 
Bicycle Crunches
When you get sick of standard crunches, you can easily mix it up by doing bicycle crunches. Lay on your back, then bend your knees, lifting both legs off the ground. Lift your upper back and neck off the ground by a few inches into a crunch. You will then move your legs out, back and forth, while extending them in a bicycle form. Try to do 10 sets, take a break, then see if you can do 10 more.