'The Book on Mental Toughness' by Andy Frisella definitely caught my attention. From what I've gathered, Frisella's work is all about building resilience and grit, which resonates with a lot of folks in the entrepreneurial and fitness communities. Now, about the PDF version—I haven't stumbled upon an official release in that format. Frisella's content is often tied to his '75 Hard' program, and his books are usually available through platforms like Amazon or his own site.
That said, I've seen some shady PDF copies floating around on sketchy sites, but I'd seriously caution against those. Not only is it unethical, but you also miss out on the full experience—workbooks, community discussions, and sometimes even bonus materials that come with legitimate purchases. Plus, supporting creators directly ensures they keep producing the content we love.