Serious climbers would be wise to train and climb in accordance to the cornerstone principles of the field of Exercise Science. For example, knowledge of the "SAID Principle" (Specific Adaptation to Imposed Demands) can be leveraged to maximize the effectiveness of your training for a specific climbing goal or dream climb.

The SAID principle explains that a certain exercise or type of training produces adaptations specific to the activity performed and only in the muscles (and energy systems) that are stressed by the activity. For example, running produces favorable adaptations in the leg muscles and the cardio-vascular system. However, the muscles and systems not stressed show no adaptation; so even heroic amounts of running will produce no favorable changes in, say, the arms. Of course, the adaptations that result from running do transfer somewhat to other sports that depend on the same body parts and systems (e.g. mountain biking). Bottom line: the SAID Principle demands that effective training for climbing must target your body in ways very similar to climbing (e.g. in body position, muscles used, energy systems trained, etc).

Similarly, your body adapts in a specific fashion to the specific demands you place on it while climbing. If you boulder a lot, you will adapt to the specific skill and strength demands of bouldering. If you climb mostly one-pitch sport routes, you adapt to the unique demands of zipping up, say, 30 meters of rock before muscular failure. If you primarily climb multi-pitch routes or big walls, your body will adapt in accordance to the demands of these longer climbs. Or, if your outings are alpine in nature, your physiological response will be specific to the very unique demands of climbing in the mountains.

The vitally important distinction here is that while all these activities fall under the headline of "climbing," they each have unique demands that produce very specific physical adaptations. Therefore, the training effect from regular bouldering will do nothing to enhance your physical ability for alpine climbing. As shown in the table below, the specific demands of sport climbing are much closer to those of bouldering. Consequently, the adaptations incurred from frequent bouldering will carry over well to sport climbing (especially short sport climbs) and vice versa.
 

Continuum of Climbing "Sub-Sports"
Bouldering	Sport Climbing	Multipitch Climbing	Big Wall Climbing	Alpine/ Mountaineering

Due to the SAID principle, your practice and training on the rocks should be spent mostly on the type of climbing in which you desire to excel. It is no mistake that the best boulderers in the world rarely tie into a rope. Likewise, the best alpine climbers spend little or no time working on 30-meter sport routes. Targeting your training on the specific demands of your preferred form of climbing is the essence of the SAID Principle.

In the end, you must make a philosophical choice whether you want to specialize--and, therefore, excel--in one of the climbing "sub-sports," or become a moderately successful all-around climber. Certainly, there is equal merit and reward in both approaches.

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(Andrea Pesca bouldering at Morrison, CO. Courtesy of StewartGreen.com)