Plato, Laws 830d

ψυχῆς καὶ παίδων καὶ χρημάτων καὶ ὅλης τῆς πόλεως; καὶ ταῦτα δὴ φοβηθεὶς αὐτῶν ὁ νομοθέτης τὰ πρὸς ἀλλήλους γυμνάσια μὴ φαίνηταί τισιν γελοῖα, οὐκ ἄρα νομοθετήσει, στρατεύεσθαι προστάττων μάλιστα μὲν ἑκάστης ἡμέρας τά γε σμικρὰ χωρὶς τῶν ὅπλων, χορούς τε εἰς ταῦτα ἅμα καὶ γυμναστικὴν πᾶσαν συντείνων, τὰς δὲ οἷόν τινας μείζους τε καὶ ἐλάττους γυμνασίας μὴ ἔλαττον ἢ κατὰ μῆνα ἕκαστον ποιεῖσθαι προστάξει, ἁμίλλας τε πρὸς ἀλλήλους ποιουμένους

And so is their lawgiver, through fear lest these training-bouts may appear ridiculous to some, to refrain from laying down laws whereby he will ordain field-operations, of which the minor kind, without heavy arms, will take place daily, if possible,—and to this end both the choristry and all the gymnastic shall be directed,—while the others, as a major kind of gymnastics in full armor, he shall order to be held at least once a month?