For this exercise, you want to place your forearms flat with your hands and wrists protruding off the edge of the bench. If you use a standard workout bench, you can simply kneel to the side of it in order to rest your forearms on the bench—just make sure to put something down to cushion your knees. In order to balance the weight, you want your hands roughly shoulder-width apart to form your grip on the barbell. To start, use a standard grip with your palms facing upward. Again, the ideal amount of weight is going to vary by person. You should aim for an amount that allows you to do twelve-to-fifteen repetitions before tiring out. The starting position is going to be with your wrists lowered so that the barbell is hanging low in your grip. With a slow, controlled motion, you want to curl the barbell up and toward you. By moving the barbell slowly, you maximize the gain on each repetition. You want to curl your wrists all the way, bringing the barbell as close to you while only using your wrists as possible, before letting it back down. At the apex of this motion, you will feel the hard squeeze in your forearms. As with the individual wrists routine, you want to do twelve-to-fifteen reps in your set before stopping. If you cannot do this many, try curling less weight. This is another workout that you can do with either upward or downward curls. To work a different forearm muscle group, turn your arms over on the bench so your palms face downward. Then lift the barbell back up and do the curls so you can see the backs of your hands.

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Write a summary of the previous text in Vietnamese:
Ngồi đặt cẳng tay trên chiếc ghế dài. Nâng tạ đòn bằng cả hai tay. Hạ thấp cổ tay. Cuốn tạ lên hướng về phía bạn. Tập 12 -15 nhịp. Lật cánh tay lại và cuốn cổ tay xuống.