When I joined at 17 I weighed 168lbs at 70.5" after OSUT Infantry I probably arrived at my first assignment just over 170lbs soaking wet. By the time I was 20 I weighed 180lbs could bench upwards of 280 and pretty much stayed that way for the next eight years. Then I went SF at 26 was an inch or so taller at 71.8" and a solid 185lbs. Weight fluctuated between 190-200 over those 13-years depending on lots of things. Always noticed that I could run faster at the light end and ruck better at the higher end.
IIRC I remember my Robin Sage ruck with M5 bag and LBV coming in at 168lbs combined. (As much as I weighed when I joined the Army.) Only two or three other times we had to leave stuff or bundle it to make jump weight. Can't ever recall having a ruck that weighed less than 80lbs and my LBV always hit the scales at 45-50lbs.
Schools are easy! EIB road march was more of casual half-marathon with lunch and cookies.
Now I'm just a FOG (Fat Old Guy) at 71.4" and 215ish. With chronic LBP and hip dysplasia