If you feel that your arms are too thin, you can make them gradually thicker by doing systematic functional exercises, especially strength training, for a period of time. While doing strength training, make sure to increase protein intake, as well as carbohydrate intake, so that energy intake is greater than energy consumption. Together with systematic upper limb strength training, the circumference of the arms can be significantly increased after about six months. It is recommended to train biceps and triceps as well as forearm muscle groups, the main movements such as barbell bending, dumbbell bending, supine arm flexion and extension, straight arm press and other exercises biceps and triceps. In addition, there are arm wrist flexors, wrist curls, exercise forearm muscles, as long as adhere to a period of time will certainly have a very good improvement.