I quit climbing almost 2 decades ago but I was lucky enough to climb with some guys who had made some long hard routes back in the day and they mostly had terrible habits and diets. Most of the drugs they used were the opposite of performance enhancing.
There was, for example, an El Cap veteran who stole all the morphine from my emergency medical kit and spaced out for 2 days after making a cracking new big wall route in Greenland. Or there was the vegan hippy who swore by homemade hummus and magic mushrooms but always had tendon issues (probably because he had not got enough protein to mend himself). Then there were old boys who had climbed with Brown and Willans and taken Dr Tom Patey's big pink pills. They drank till they puked every night in Chamonix before smashing the Bonatti pillar in big boots with no harnesses and only pegs for pro. (The worst bit of that route I was told was when they dropped the last packet of fags). These guys all did some climbing that most people today only dream of.
I learned from these assorted reprobates that the things that make a great long route climber are;
1. A huge experience of every move type you might encounter, so you are operating low stress on stored schemata of movement. (This is the key to long free solos).
2. A degree of reserve strength -so you are only using a small part of your capacity but this must come with minimal weight
3. Cool realistic confidence. You can't afford to make mistakes far away from gear and help but you also can't afford to waste your limited energy/ time/ weather window hesitating to double check many moves before committing
4. The ability to sleep somewhere uncomfortable, not wake at 3 AM to think about the morning's crux pitch and rise reasonably recovered.
I climbed with Frenchmen who could knock out 8 grade sport routes or A4 pitches all equally fuelled by the traditional 3 cs -cafe, croissant, clop. I learned from the pros -only 1 cafe before a route with small holds or you shake too much and you might need a few clops for a hard aid pitch, however add cannabis to the first clop and you don't worry so much about skyhooks and lead heads blowing.
Why recount anecdotes about yesterday's dirt bags? Well I think the dirtbags' successes suggest that the best spaces for PEDs on big scary routes are in the recovery and the nootropic angles. You don't actually need awesome athleticism or great health to climb very well indeed. The key on hard and long trad routes (beyond just touching miles of stone first) is not in pushing your peak performance (you did that earlier on countless short routes) but in eliminating your stress and poor performance, so you still have plenty in reserve for the harder stuff.
So I would suggest;
Anything that will improve sleep quality
Good antioxidants in your food
Good mitochondrial performance -you need to run aerobically in the mountains but on steep walls you still need to clear by products of anaerobic climbing fast to be ready for the next pitch. Mitochondria love burning lactate that otherwise your liver will have to deal with and its busy dealing with the stress of it all.
Buffering against the hydrogen ions that come with lactate on more athletic routes
Confidence and relaxation without loss of focus or increase in stress hormones
Tendon strength building and repair
Avoid stimulants beyond one coffee in anything but the alpine arena where its basically an aerobic challenge with technicalities way below your usual grade. Many dirtbags had cautionary tales of trying to push their performance with stimulants (amphetamines, speed, coke) and getting horribly unstuck when they found themselves pumping out far above gear, somewhere they should never have gone.
And yeah the guys said Wolfgang Guillic was on steroids. But then again its little wonder. No one else had a body anything like that back then. Anavar?
