What type of climbing? Pumpy rock routes? Glacier or ice? Scrambles? Hillwalks?

Assuming you can't get out and do similar activities frequently (as is often the case), then yes, you've got to workout by simulating those activities. Many of us don't have time to get out and workout (or even climb/hike) all the time, so we've got to make the most of the short windows we get.

When I was training for Rainier or Mont Blanc my workouts consisted of a lot of running (if you can't go for a long time, then go as fast as possible), and running intervals. Then running hills and occassionally using the stairmaster in the gym. Also did squats, kettlebells and calf raises.
If I only had 45 minutes to workout (common), then I'd do a short warmup, then 4-6x 400-800m repeats on a track. Then some lunges or kettlebells. Sometimes that'd be all I could fit in, a few times a week, and it worked well.

For ice I tend to incorporate a lot of pullups, calf raises, and hangboard.

For rock-routes, the hangboard, pullups, and pushups get used more.

For general fitness and maintenance, do whatever you like. Run, bike, swim, hike, climb, lift, tennis, basketball, ski. Mix it up.

As I've gotten older (not that I'm very old, relatively), I realize that if you don't do something for a while it is much harder to pick it back up.
I went out and shot some hoops a few weeks ago (first time in probably 2 years), and damn if my knees didn't ache for about 3 days afterwards!

Hiking steep trails will get your heart, lungs and legs in shape for approach hikes, backpack trips, etc. Doing it at high elevation in the western US will give you some experience at altitude. Backpacking or hiking steep trails with a pack will make you stronger but it did wear out my knees over the years. Don't run downhill - not good for the knees. Don't be overweight - it's hard on your knees.

Cycling is good - I prefer a mountain bike due to less bending of the back - now that my back is not the best. Running is great but I think it's hard on the knees - I can no longer do it.

Do exercises to strengthen and maintain flexibility of your back. Here is one website. I paid my physical therapist to help me with a sore back and many of the exercises I was told to do are on this page - they did help me: http://www.bigbackpain.com/back_exercises.html

Advice from surgent on a strong core is good. Very important.

Is a strong core that important? Just to be a bit contrarian but I have never come of a hill and thought, gee I wish my core had been stronger. I usually wish i had spent more time training my quads or shoulders.

I have weight issues ... What would be the ideal bodyfat percentage ...
For summer and rockclimbing pretty low, for endurance long trailruns a bit more and longer periods in winter (3-4 days) even more. But what is ideal?
Anyone an idea?

I am not sure, but if you are talking about doing the European Highpoints, you might also be considering how much body fat you will have at the end of it. With all of the drive time, loss of sleep and being in a rush, you may not be able to get enough food to maintain your body fat percentage. For Elbrus I don't think it would hurt to have fat reserves because the altitude will make you not want to eat and you'll lose some weight. Same thing for the other Caucasus highpoints. Then going into the rest of Europe you won't have too much trouble, but reserves wouldn't hurt there either. Ideal, I do not know...I would think it varies by individual.

Core strength is important, mainly because it keeps your form good and allows you to be more efficient. I'm not saying that more situps will make your quads less sore. But a strong lower back, lower abs, hip flexors, and gluteus minimus (the small muscles along the side of your hip) keep you aligned.
I was having some knee pain, and stretching my hamstrings and strengthening my gluteus minimus cured it.

For your ideal bodyfat percentage (body composition), the easiest way to determine if your composition is right is to look at yourself in the mirror. Other than perhaps Iditarod, I don't know of many times that having a higher percentage is beneficial.... It's cheaper to lose 2lb of fat than it is to lose 2lb from your pack.
And if you're on the other end of the scale, don't bother posting because I don't want to hear about your struggles to get out of the 5% zone!

radson wrote:Is a strong core that important? Just to be a bit contrarian but I have never come of a hill and thought, gee I wish my core had been stronger. I usually wish i had spent more time training my quads or shoulders.

On top what has been said for keeping good form, it also depends on your plans.

If you plans is glacier slogging or backpacking, a stong core can help prevent back injuries.

If you are talking more modern alpine stuff, core strength is essential.

Andrew Rankine wrote:I am not sure, but if you are talking about doing the European Highpoints, you might also be considering how much body fat you will have at the end of it. With all of the drive time, loss of sleep and being in a rush, you may not be able to get enough food to maintain your body fat percentage. For Elbrus I don't think it would hurt to have fat reserves because the altitude will make you not want to eat and you'll lose some weight. Same thing for the other Caucasus highpoints. Then going into the rest of Europe you won't have too much trouble, but reserves wouldn't hurt there either. Ideal, I do not know...I would think it varies by individual.

Wanne do Elbrus in less than a day ... So no need to be overfat lol
Looking into nutrition at the moment ...