"There's no gym for your face"
There's no gym for your face. This is an expression that means those with an ugly face can't rectify this situation through exercise, and therefore it's over for them.

Well, it makes only a little sense. "There's no gym for your face" -- it's just not completely true and here is why:
1) Once you are regular in the gym (or just at home doing sports) or just use another way (outdoors activities) to improve your body, then your face could improve, at least a bit, too. For example when one is a fat person. After losing weight he or she, usually, will be more attractive (according to the most of the nowadays tastes around the world).
2) Sport keeps you younger and healthy (in some degree). Healthier and younger face is prettier than ill and old face, isn't it?
So, gyms (and the sports at all) are useful in a certain degree for your faces.
Something related:
https://www.webmd.com/fitness-exercise/news/20091201/molecular-proof-exercise-keeps-you-young#1 
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