The arm is mainly composed of forearm and biceps brachii, triceps brachii and deltoid muscle. Hold the dumbbell with one hand (hold it more tightly), sit and bend over, stick the arm holding the dumbbell on the inner thigh for arm flexion and extension, and repeat it to effectively practice the forearm muscles. The biceps brachii is mainly pulled, 1. You can bend and stretch the dumbbell with the big arm, but don't put it last when stretching, so that the biceps are always stressed. Also, you can use Schwarzenegger's method, which has a nice name of 2 1 salute, that is, when you bend over and stretch the dumbbell arm, because it is 65438 from straight to bent. 2. Shoulders do pull-ups. Triceps brachii is the main push, 1, push-ups; 2, bench press, 3, do arm flexion and extension on the parallel bars; 4. The one-arm dumbbell arm behind the neck bends and stretches. The deltoid muscle is divided into three bundles: anterior, middle and posterior. You can do push-ups and tiptoe bench presses to practice; In the middle beam, grab the dumbbells with both hands and hang them on both sides of your legs, then do a 90-degree flat lift and repeat; Behind, grab the dumbbell with one hand, bend your body forward 90 degrees, and lift your arm back up. Repeat. Each group does the limit. Remember not to do it every day, but every other day. Every time you do anaerobic exercise, you should destroy your muscle tissue as much as possible, and then use enough time and nutrition to repair the damaged muscle tissue and let it grow. To put it bluntly, muscles grow out at rest after anaerobic exercise. Only scientific fitness can have perfect muscles. (Changyang Xiaohua is original, don't copy, never be anonymous, despise plagiarism! )