@AlfhedilUm, acccording to this source, WW2 soldiers were already carrying some 40 kilos of equipment and gear.
Tripling it won't be possible, neither it makes sense.
An armor which doesn't cover mot of the limbs or such but 5mm thick would weigh around 25 kilos.
So at best you're raising their load to 65 kilos (which is of course pretty ridiculously lot),
While that's interesting and a cool source and all, the average WW2 soldier also marched in their equipment. The Stahl-Männer do not march, instead utilizing APCs to get to the combat zone they are needed in. So while the kit is heavier than the standard kit, the troopers are not nearly as strained as you make it out to be. In fairness, I may have been over-zealous in terms of weight.
Then again, this is a setting where elves ride griffins into battle. -shrugs-
@Alfhedil
Also, that's an absurdly large army for a nation of that size. I think Voltus said the rule was only around 6% of the population could be in the military, but even that is pretty ridiculous in my opinion. I think you'd be hard pressed to find many examples of standing armies comprising more than 3% of the population.
It's a nation where service in the military is required, by law, though more so encouraged by the militant police. Of course their military is not going to be on the same level as another nation with a standing army. One must also take into consideration the intense paranoia they have in regards to their neighbors.