Modelling is not as tough on the body as football, there's no high risk of getting a serious injury, or having people scream derogatory things at you while you are working. I don't blame Ronaldo if he wants to quit football while he's still healthy and doesn't have pain when he holds his children. There's so many other jobs safer things he can do because it's not like he needs to do it for the paycheck he's already rich for life rolling in cash.