There are many things about climbing that are super confusing to a newbie: Why are the shoes so tight? Why do climbers sometimes scream when reaching for a hold? Why is that person standing under a route whispering and waving their hands in the air, is it a magic spell? why not just use a ladder?
What confused me the most when I started was the chalk. Some people seemed to hardly use it, others almost literally threw it around themselves. There are little bags people wear on their waists; little bags they leave on the floor; big buckets left on the floor; and most confusingly of all, some kind of gross liquid stuff that I was pretty sure was only used by competitors in ‘The World’s Strongest Man’. What could Dwayne ‘The Rock’ Johnson and my 110lb friend cruising up a gnarly slab have in common? It turns out, quite a lot. Because, when Hafthor ‘The Mountain’ Bjornsson and my friend put chalk on their hands they’re actually trying to do the same thing, increase friction. Unfortunately, chalk is not a magical substance that will improve your grip strength, or allow you to hold on harder or longer (if only), but what it is great at is drying out your hands.
There are some lucky people in the world who don’t seem to sweat much, or even at all, from their hands. For these privileged few the friction generated between their fingers and the natural roughness of the rock/hold will be enough to keep them on the wall. But ordinary mortals such as me (and probably you) sweat from our hands, adding a layer of lubrication between the skin and wall which basically acts as a grease, making it much harder to stay on. To avoid that extra grease layer, we can use chalk to dry out that sweat, hopefully keeping us on the wall for longer (when climbing in Vietnam I sweated so much inside my shoes, I seriously considered chalking up my feet, but that’s a different story).
But remember, because we’re only using chalk to dry our hands, we only need a little, once they’re dry more chalk does not equal better climbing. After all, we brush down holds if there’s too much chalk on them, because excess chalk reduces friction, the opposite of what we’re looking for.
Liquid chalk is a little different, it’s a mix of chalk and isopropyl alcohol which basically acts as an antiperspirant for your hands, evaporating off the sweat and leaving your hands drier for longer. Mostly it’s used by climbers at the beginning of a session in order to create a “base layer” of chalk that’s topped up with powdered chalk over the session. It’s particularly loved by people climbing long routes who don’t want to have to stop every few minutes mid-route to chalk up. However, a small percentage of people find it irritates the skin, drying it out, but this will stop as soon as you stop using it.
Personally, I’ve always had problems with sweaty hands so finding liquid chalk was a minor miracle for me. Over the summer I use it once or twice over a session, topping up with dry chalk as needed, especially my fingertips. The only real problem is that I now have one less excuse as to why I came off that route again.