Question:
being double strenuous on your own body because you're pushing it yourself

Does it follow that "It's hard on your body to go for that long of a walk."?
Answer:
it is not possible to tell

Question:
It was the main entrance to the castle, and a formidable obstacle to the enemy.

Does it follow that "Enemies rarely attempted to enter through the main entrance of the castle, but you can recreate an attempt while you are there."?
Answer:
it is not possible to tell

Question:
I had intended to become a land girl, a postwoman, and a bus conductress by way of rounding off my career but the Armistice intervened!

Does it follow that "It was only the end of the war that allowed her to explore her career options."?
Answer:
no

Question:
And they look so cool.

Does it follow that "They look neat."?
Answer:
yes