I'm joining the buff Robin train with hcs on the way.
She constantly forgets how strong she is/how big her muscles are. Like, she'll be asked to open a jar or something but will immediately use an excessive amount of force because she forgets that she's actually strong and doesn't need to take a whole gulp of breath when opening a jar.
Also, she sometimes forgets that her muscles are typically too big for long sleeves and has ripped the seams of many shirts.
When she does remember her muscles, she takes the pleasure of showing them off to a particular pretty girl. She'll unnecessarily flex a bicep or a thigh when doing any kind of normal human activity that does not require flexing muscles. Nancy thinks it's mostly cute.
Robin offered to work out with Steve to get his ass off the couch, but after one (1) routine, he waved a white flag and simply passed out.
Robin does push-ups while Nancy rests or sits on Robin's back reading a book and/or telling Robin about her day at work.
Nancy and Robin run together most mornings <3 (bonus: Nancy has more stamina and pokes fun at Robin for being weak in the knees 5 minutes into the run :])