TreVulan The plank is always necessary for a great ab workout. This exercise can be done both at home and gyms. To do this exercise, bend down on your hands and knees. Place your elbows on the ground and slightly curl your toes. Contract your abdominal muscles and then slowly lift yourself off the floor. Make sure your lower back remains elevated. Do not let you lower back dip otherwise the exercise will not work. Hold the position as long as you can and then rest. Repeat as necessary.
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