Exercise can reduce body fat, but no specific exercises causes fat loss only around the ankles. Attempting to lose weight from one area of the body is also known as "spot reduction" and, according to Yale Scientific, is impossible due to the way the body burns fat during exercise.
During exercise, the body breaks fat down to use as energy and releases it into the bloodstream, as stated in Yale Scientific. The fat that is burned can come from anywhere in the body. Doing specific exercises to slim the ankles is not likely to burn many calories. The best course of action is to engage in regular cardiovascular exercises, especially high-intensity interval training, which burns more fat than traditional cardiovascular exercise, explains Yale Scientific.