Women with thick arms may be caused by the following reasons: First, lack of exercise. Most cases in life will use the small arm, and the muscles of the large arm is difficult to move, which will lead to fat accumulation in the large arm, so it will produce obesity. Second, incorrect sitting posture, often hunchback, will make the oblique muscles, deltoids and triceps in a relaxed state. Time will be piled up in the arm and shoulder back position, so the arm will become thick. Third, the inner arm obesity, which is one of the manifestations of the thickening of the arm, mainly because the arm lymphatic is not smooth, resulting in the accumulation of water, the formation of swelling. Fourth, a long time a lot of heavy lifting, because often use the arm to carry heavy objects, will make full use of the muscles on the arm, will make the muscles become more developed, resulting in thicker arms. It is recommended to let the body maintain a moderate amount of exercise every day, no matter which part of the body can play a good role, while paying attention to maintain a reasonable routine, as well as eating habits.