Hektore

I like to climb as well, and my current understanding is the best workout for climbing is climbing. Treat climbing like a workout when you go, especially bouldering because it is so short and high intensity. Do sets, with rest intervals the works, don't go two days in a row, and don't overdo it when you're there.

For workouts separate from climbing, typically you want a lot of upper body focus, not on the lower body. I don't think I've ever heard of someone failing on a route because of leg pump. For climbing in general (as opposed to bouldering specifically, but much of it still applies), the book how to climb 5.12 is pretty helpful. A friend of mine owns it and while I haven't read it cover to cover the parts that I have read contain good, concise information. Also, I don't know your living arrangment but you can usually build a pretty nice campus board relatively cheaply. They don't take up much space and provide you with a great climbing-oriented workout opportunity if you can't get to the gym(either or them) all the time. If you aren't sure how to build/use a campus board there is a nice guide(.pdf) at metolius.

Also something I have found to be incredibly helpful is completing a route multple times. Many people do a route once and never even look at it again, but if you rework the problem multiple times (over a few days) you will better commit the movement to memory, refine it so you use less energy and train the muscles used specifically for that movement.

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