Hello...I am not exactly sure what surgery you are going to have so it makes this question hard to answer. However, this question is under the topic of tummy tuck so I am going to answer this question like it is for tummy tuck. During a tummy tuck, there is a lot of important anatomy one needs to see in order to maintain symmetry and to do the operation well. When I perform tummy tucks on my patients I combine liposuction in order to achieve far superior results than tummy tuck alone. This means I lipo all the way up to the upper abdomen which is just below the breasts. If a patient was to wear a sports bra during surgery that would be in the way of surgery so that would not be possible. In fact, for almost any surgery above the waist you would not be able to wear a sports bra. For surgery confined to below the waist it may be ok to wear a sports bra but that would depend on your surgeons preferences. However, this is something you should speak to your plastic surgeon about to see what his thoughts are. Hope this helps and good luck!Ankur Mehta MD