Thank you for your question. There are things that can be done to improve the contour of the upper arms. Diet and exercise can help improve the contour of the upper arm. However, if the area on your upper arms is due to excess skin then diet and exercise will have minimal impact. The best way to remove significant excess skin is through a brachioplasty (arm lift), which is a surgical procedure in which the excess skin is removed. If there are just stubborn pockets of fat then either liposuction or coolsculpting may be beneficial. Your best bet would be to come in for a consultation with a board certified plastic surgeon and see what is the best way for you to achieve your aesthetic goals. Good luck.
Unlike muscles, you cannot target specific fat areas to go away. To lose fat in your arms, you would have to lose fat overall. You can target muscles in your exercises, but there are no exercises that will specifically get rid of fat. The gold standard for fat in the arms is liposuction, but the concern would be hanging skin after the fat is removed. There are non-invasive techniques to get rid of fat, but they provide limited amounts of fat that can be destroyed. I would recommend you see a reputable plastic surgeon to see what your best options are for your arms. A good surgeon should be able to offer several options, along with the pros and cons of each, and whether he/she think that option will meet your goals. Good luck!