Bend your elbow 90 degrees, and try to keep your wrist in a horizontal posture, with the center line of your palm and the center line of your forearm.
Keep straight. The waist of the lower body is straight, the knees naturally bend 90 degrees, and the sitting posture with both feet on the ground is maintained.
2. Be sure to choose tables and chairs with ergonomic design, use special chairs, and follow the "three" when sitting on them.
Right angle ":the first right angle is formed at the knee under the table, the second right angle is formed at the thigh and back, and the arm is at the elbow joint." "
Form a third right angle. Lean your shoulder blades against the back of the chair, put your shoulders down and keep your chin away from your neck. Keep your eyes straight ahead, preferably with a supported chair back and armrests, and the height can be adjusted.