Thin privilege is being congratulated or praised for doing well in sports, rather than your opponent(s) being berated and mocked for being so bad that they lost to a “fatty”.

I am active and fat, and I have been my whole life. I’ve been a dancer, an athlete (shotput, hurdles, long and high jump), a boxer, and I’ve competed on a national level in swimming (winning two medals). I was rarely congratulated in earnest without a “…for someone your size” tagged on to it. I was hated by many for doing well because it apparently made them look bad in comparison.