Justifying or defending something based on a quotes is recipe for contradictions and disaster.

For every quote, you can find an equal and opposite quote.

"Actions speak louder than words." vs "Pen is mightier than the sword."

"Many hands make light work." vs "Too many cooks spoil the broth."

It's like the bible, I can find a quote to justify pretty much anything. And then I can find a quote to denounce the same.

I think it's silly to advocate for physical activity with a quote. I think it's better to defend physical activity because it keeps you healthy physically and even mentally. I used to be a big quote collector ( from benjamin franklin to the bible ). I'm not any longer.