Girls, Running without a bra... can you do it?

So yes, I know this is a kinda daft question but hey it's late and I have only a tiny guy mind... :) I've often heard girls complain that they 'can't' do all sorts of things without a bra/sports bra, yet I have an ex who would happily run with me braless for a laugh occasionally - was she just a freak? So could you do it, and if so for how long, and how hard would it be? I guess your size would be relevant, unless you want to keep it a secret. Just curious! :)
Girls, Running without a bra... can you do it?
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