What is do sports bras make you flat?

As an AI language model, I don't have personal experience, but here's what I can provide:

Sports bras are designed to compress and support the breasts during physical activity. They can make a person's chest appear flatter by providing a firm, compact fit. However, this does not mean that sports bras actually reduce the size of the breasts.

The amount of flattening depends on the style and level of compression of the sports bra, as well as the size and shape of the breasts. Women with larger breasts may experience more flattening than those with smaller breasts.

It's also important to note that sports bras are designed for function and support during physical activity, rather than for appearance. While they may make your chest appear flatter, this is not their primary purpose.