Conditioning
The bulk of mountain climbing, even in ascents with very technical sections, is all about aerobic fitness: the ability to work at a very moderate pace for long periods of time. BREATHE! Yes, you will do yourself worlds of good by simply training your body to breathe efficiently, increasing your aerobic capacity. This is especially true when climbing at higher altitudes. That being said, any training regimen involving regular aerobic exercise is great for general mountaineering. Sure, if you are lucky enough to live near mountains, getting aerobic exercise by hiking up hills, skiing, biking and so forth is excellent sport specific training. But you can also train for this just about anywhere, even in Florida.

By doing just about any aerobic activity inside or out, you can get your body into better aerobic fitness. How much and how far? I recommend longer and slower, thus improving your overall aerobic base. Certainly not everyone can go work out on the stairmaster for two hours a day, but 45-60 minutes of aerobic activity three to four times a week is great. By keeping a slow pace you will improve your base aerobic fitness, but it also has the added bonus of training your body to burn fat a source of energy. This is great for mountaineering where you will usually be keeping a slow, but steady pace and are always able to consume enough food to keep up with the energy demand. In order to really reap the benefits of this type of training, you should begin at least 4-8 weeks prior to your planned ascent. As an added bonus you will most likely be losing some unnecessary pounds to boot! I recommend incorporating general aerobic fitness into your lifestyle if mountaineering is a hobby you enjoy.

Check out a sample training routine for mountaineering here.

You may also want to include about one hour of strength training a few times a week if your are unable to get out and climb. Weight training will help prepare you for the demands of the occasional powerful move encountered and help you avoid injury. A well-rounded weight training routine is most recommended for general mountaineering. A good one would include: squats, leg presses, calf raises, abdominal crunches, lat pulls, rows, bench press, and shoulder press. In the weight room, aim for medium resistance, unless you are a seasoned training junkie. I recommend doing about two three sets of each exercise, completing about 8-12 repetitions per set.

For those really serious about getting fit, consider purchasing a heart rate monitor. This doodad is very handy for getting the most out of your training. With a heart rate monitor you can target specific heart rate zones that are best for certain types of training. The best rate for general aerobic conditioning will be keeping a pace in the 60-70% training zone. The % "training zone" heart rate is calculated using the Karvonen Formula, which is as follows:
(maximum heart rate – resting heart rate) X % "training zone" heart rate
+ resting heart rate = training heart rate

Example: For an individual with a maximum heart rate of 180 and resting heart rate of 50, the calculation for the 60 percent training zone would be:
((180-50) X 60%) + 50= (130 X 60%) + 50 = 78 + 50 = 128
And for the 70% training zone it would be: (130 X 70%) + 50 = 91 + 50 = 141
Therefore, this individual would want to maintain a level of exercise with his or her heart rate between 128 and 141 in order to stay in this aerobic base conditioning zone.

You can also keep track of your recovery and overall fitness by monitoring your waking heart rate. If you waking heart rate is not back near the normal, then you likely need another rest day or perhaps you have an illness coming on.

Technique
Technique training is perhaps as important as any other aspect of physical training. To work on this, consider getting out onto some off trail areas for hikes. Most climbs end up off trail and on rugged terrain. It is amazing how well we as Westerners have adapted to walking on relatively flat and clean surfaces. When we get out on even the easiest of cross country terrain we are often loose any surefootedness. By simply being able to move more efficiently in the mountains and on rough, irregular terrain, we save energy even with no gains in general fitness. Spend some time walking around in places where most people don’t so that you are able to move more efficiently in the mountains.

Finally, lets talk a little about technical climbing as it relates to mountaineering. If your goals are to just get up the big summits then you are better off spending your time with aerobic base conditioning and off-trail hiking. If your goals include climbing to the summits via more technical routes than it certainly would behoove you to hone your skills in this department. You certainly do not need to go off to the gym and start weight lifting to develop superhuman upper body strength to get up technical mountain routes. However, you should spend some time at the crags or climbing gym to improve your technique in the type of climbing you expect to encounter. By becoming more proficient at the specific movement skills required of your upcoming ascent, be it rock climbing, ice climbing, or ascending fixed lines, you will be able to move more efficiently, use less energy and be faster. If you are going to climb the Matterhorn, for example, you do not need to become a 5.10 rock climber, but feeling comfortable on a variety of 5.6 would be a benefit. As well, you do not need to be able to climb vertical ice, but if you did spend some time learning ice climbing skills you would likely feel much more comfortable when wearing your crampons on the moderate snow field near the top.

So, suffice it to say that augmenting your regular fitness training schedule with the occasional day at the crag will help improve your overall mountaineering ability. Hence better chances of success on the technical mountain climbs.