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Actually, with today's diets, training, and physical education, soldiers are in FAR better physical condition than in any time in history. Ancient/Medieval period armies had two types of fighting man: One was a commoner that was pulled into military service on an "at need" basis, and had little in the way of real martial skill. They were drafted and put into simple infantry units (pikemen, slingthrowers, etc). Most of their muscle was developed by daily tasks (farmers, blacksmiths, etc). The other was a class of military lifers, in the middle ages, general an aristocracy, but not always. Many of these guys were indeed, incredible soldiers, but still suffered from the many problems of the past -- poor, limited diets, a rudimentary understanding of biology. While I'm sure an armored up knight in full plate could stand a pretty good chance in a close quarters fight with a modern soldier (and most likely win), the level of training in today's armies is just superior across the board. Even at a squad level, soldiers are now taught tactical assessment, weapon deployment, etc, and given a broad spectrum of skill training (including close quarters combat). I don't doubt their bravery (of any time period), or their power, but the technological and intellectual advances give the edge to today's soldier. But no, they weren't tall. Or generally all that healthy due to the poor understanding of sanitary conditions or of medicine*. The average height for a man today is far above what it was in the middle ages (5'8 as opposed to 5'3), and taller than in even advanced ancient civilizations as well. Edit: Wether you believe it or not, the lack of height is a historically documented fact. Go to anywhere with surviving medieval or earlier armor, or surviving civilian clothing. Or statues. Or paintings. Or extant documents of measurements. Or, just go inside an old house and notice how low the ceilings are. They all conclusively prove this whether you want to accept it or not. Besides, why on earth would you want short soliders? That makes no sense from a martial standpoint. Taller units are more intimidating and have longer range with melee weaponry, both well known and well documented things (in fact, many armies through history had elite units with minimum height requirements). Also, Peter the Great was not "medieval". He was born in 1672, WELL into the Renaissance (as in more than 100 years into it), what most historians consider the end of the middle ages, and was ROYALTY, meaning he did not suffer the same extent of malnutrition most people did in earlier times. And at 6'8, he was considered abnormally huge, almost freakishly so. Citing an outside example of a tall person is not accurately representing the data. Abraham Lincoln was freakishly tall too, at 6'4. Just because you have the occasional one-offs (how many 7 foot people do you see every day? Yet they exist), does not make the historical evidence incorrect. Lastly, you're absolutely wrong on weapon weights. Spears do not weigh 55lbs/25kg. Not even a massive, armor piecing, HORSE MOUNTED LANCE is going to weigh that much. And an infantry sword is nowhere near 10kg. A person cannot effectively weild nor swing a 22lb sword in battle. A horsemen's Zweihander or a Scottish Claymore (both massive, two handed, full body swords) don't even weigh that much. A simple Roman Gladius or Middle Ages Bastard Sword? You're looking more in the range of 2-5kg, and even a 5kg sword is a giant, 2-handed weapon. A typical short to medium sword weighs less than 5lbs/2-3kg. This is a sadly common misconception, enhanced by the movies, and covered in the link below.