You must follow strict rules. You must stick to a rigid diet. No fancy foods. You must exercise when you're told to — in the heat, in the cold. No cold water when you want it. No wine when it's available. You surrender yourself completely to your trainer, like you would to a doctor. Then in the actual competition, you'll get covered in sand. You might dislocate your hand or sprain your ankle. You'll swallow dust. You'll get whipped. After all this suffering, you might still lose. Think through all of this first. If you still want to do it after considering everything, then go train. If you don't think it through, you'll act like children who pretend to be wrestlers one minute, gladiators the next, then trumpet players, then actors — just because they saw something cool and got excited about it.
You must act according to rules, follow strict diet, abstain from delicacies, exercise yourself by compulsion at fixed times, in heat, in cold; drink no cold water, nor wine, when there is opportunity of drinking it. In a word, you must surrender yourself to the trainer, as you do to a physician. Next in the contest, you must be covered with sand, sometimes dislocate a hand, sprain an ankle, swallow a quantity of dust, be scourged with the whip; and after undergoing all this, you must sometimes be conquered. After reckoning all these things, if you have still an inclination, go to the athletic practice. If you do not reckon them, observe you will behave like children who at one time play as wrestlers, then as gladiators, then blow a trumpet, then act a tragedy, when they have seen and admired such things.