The only way to do hard things is to show up and perform.
Sounds simple ... but it's the easiest step to skip.
Here's the thing about doing something that's never been done : it's impossible to predict the outcome. That reality is the paralysis the vast population gets stuck in. It's only when we break it down and realize we actually can't predict anything that we can replace fear with faith.
Think about it ... we hit the gas on green with no absolute certainty that the others will obey the red (my third-culture self feels this to my core). We study a career in university with no guarantee that we'll be successful at it - or even enjoy it. Olympians dedicate their entire lives to perfecting their sport with no promise of a Gold.
You just do it.
And as you do, you discover.
You discover what you're capable of. You discover where your weakness is. You discover what your fears are. You figure out pretty quick if your training was sufficient and trust me, you won't need someone to tell you if you can or cannot complete the challenge ... your mind will decide that for you.
Just before I set off to run 500KM I read a post about the run on Reddit (I was secretly stoked about it, even though 60% of the comments were negative). The question posed, "Do they really think they can do it?" For some reason when I read it I laughed at how ridiculous a question like that sounded up against a 500KM barefoot run. The laughing silenced as I realized Sheila123 on Reddit wasn't the only one who'd asked this question.
I'm not a planner ... at all. Most my trips are decided a day before departure (ironically I'm writing this while I pack for a weekend at the Coast I decided to take about 45 minutes ago). But I did have a theory : as long as my body was ready it wouldn't really matter if my 'replenishment' car overheated, half my route was on a cheese-grater road or that the supply of Kin Tape was gone by Day 2. Nor would it matter that temperatures reached 45c, that our road crew was incredibly understaffed and the AC never worked in the motorhome. Those things could've justified instant defeat ... I mean who even stands outside when it's that hot, to say nothing of bare feet smacking 125c pavement! But if you just show up ... everyday, leaving all the chaos, complaints and doubts at home, you just might experience a shift in perception that leaves you saying, "I actually think I can do this!"
And here's the thing : show up today.
Don't worry about the 63KM that needs to be run tomorrow - you'll find that strength the following morning. Don't worry about how much your foot is hurting, leave it for the Doctors when the run is over. Don't worry about impressing the crowd, just amaze yourself you'll have accomplished something worth acknowledging.
So to answer Sheila123 ...
I actually did believe I could run 500KM.
Could I back it up with a resume of successful runs and previous extreme challenges? Heck no. But stepping outside your comfort zone isn't about knowing all the answers in advance. It's about preparing yourself to the best of your current knowledge and then trusting the experience to teach you the rest. And trust me ... the only one who can determine if you can or can't do something ... is yourself.