Plato, Laws 789a

πολλῶν καὶ συμμέτρων, οὐκ ἴσμεν ὅτι μυρία κακὰ ἐν τοῖς σώμασιν ἀποτελεῖ; πάνυ γε. οὐκοῦν τότε δεῖται πλείστων πόνων, ὅταν ἡ πλείστη τροφὴ προσγίγνηται τοῖς σώμασι. τί δῆτʼ, ὦ ξένε; ἦ τοῖς ἄρτι γεγονόσι καὶ νεωτάτοις πόνους πλείστους προστάξομεν; οὐδαμῶς γε, ἀλλʼ ἔτι καὶ πρότερον τοῖς ἐντὸς τῶν αὑτῶν μητέρων τρεφομένοις. πῶς λέγεις, ὦ λῷστε; ἢ τοῖς κυουμένοισι φράζεις;

without plenty of suitable exercise, it produces in the body countless evils? Certainly. And when bodies receive most food, then they require most exercise? What is that, Stranger? Are we to prescribe most exercise for new-born babes and tiny infants? Nay, even earlier than that,—we shall prescribe it for those nourished inside the bodies of their mothers. What do you mean, my dear sir? Is it unborn babes you are talking of?