About 95% certain. Caloric intake alone was lower which meant less body mass. If you look at the clothes people wore, they were all small. They’ve dug up tunics and all sorts of stuff and you can see people were smaller on average. People didn’t have full time warrior professions for the most part (I mean there were always some that did but not most citizens). Your day to day life would have been already fairly difficult and likely running a caloric deficit unless you were specifically recruited to fight and were well fed. In those days men had to march a lot from place to place for battle and that would mean you’re running on caloric fumes. You’d be lean and strong in a strong farmer or strong metal worker type of way, but not bulky with muscle mass. People didn’t lift weights for training as much as they did for labor.

There are exceptions of course like Spartans who trained solely for battle and practiced fighting. That likely made them very tough and agile - maybe equivalent to a professional wrestler physique today with a hint of mma fighter. And you may even have had some bigger guys who were considered big for that time, but on average you’d probably be between 5’6-5’8. Archaeological evidence supports this.