This is an excerpt from Building Muscle and Performance.
Transfer for Improved Performance
The goal of exercise programming for enhanced human performance is to maximize training transfer. Some exercises provide obvious and direct transfer to improved performance in sporting actions and overall functional capacity, whereas others provide less obvious transfer - that is, indirect transfer.
Functional capacity is one's range of ability; in other words, higher functional capacity means that a person can perform a broader range of specific tasks. Within this framework, the four primary types of exercise addressed in the functional-spectrum training system (again, total-body power, cross-body, compound, and isolation) are each classified as either specific or general based on how they transfer functionally. These two categories of exercise - specific and general - offer different benefits; more specifically, each type benefits certain interdependent components of fitness and performance that the other category may miss.
Specific exercises provide obvious and direct transfer to improved performance and functional capacity because they are based on the principle of specificity. That principle has been defined as follows by Dr. Everett Harman in the National Strength and Conditioning Association's Essentials of Strength Training and Conditioning (2000, 25-55)
"The concept of specificity, widely recognized in the field of resistance training, holds that training is most effective when resistance exercises are similar to the sport activity in which improvement is sought (the target activity). Although all athletes should use well-rounded, whole-body exercise routines, supplementary exercises specific to the sport can provide a training advantage. The simplest and most straightforward way to implement the principle of specificity is to select exercises similar to the target activity with regard to the joints about which movement occur and the direction of the movements. In addition, joint ranges of motion in the training should be at least as great as those in the target activity." (1)
Specific exercises create a more ideal environment than general exercises for enhancing the specific force-generation and neuromuscular-coordination patterns of the targeted athletic movements.
General exercises are essentially conventional strength-training exercises and may consist of either compound or isolation movements using free weights, cables, or machines. In most cases, general exercises create a more ideal environment than specific exercises for stimulating increases in overall muscle strength and size. Therefore, these applications offer general transfer into improvements in human performance by increasing muscle hypertrophy, motor-unit recruitment, bone density, and connective tissue strength, which can improve overall health and reduce injury risk.
On the other hand, because these exercises do not necessarily reflect the specific force-generation and neuromuscular coordination patterns of many common movements in athletics, their positive transfer into improved performance potential is less obvious. This fact has led some personal trainers and coaches into mistakenly labeling them as "nonfunctional" and therefore not valuable. That is a false belief.
Granted, the further an exercise gets away from replicating the specific force-generation patterns of a given movement, the less directly it carries over to improving the neuromuscular coordination of that movement. However, this fact doesn't make an exercise bad, and it certainly doesn't make it nonfunctional. It simply means that the less specific an exercise is, the more general it is.
For this reason, instead of referring to some exercises as "functional" - which implies that others are "nonfunctional" - it is more accurate (and less confusing) to refer to exercises as either general or specific. Each of these types offers a unique set of benefits that transfers into improvements in performance and overall functional capacity.
Common Confusion Associated With Specific Exercises
Working on sport skills with specific exercises is not the same thing as working to improve specific force-generation and neuromuscular coordination patterns, which transfer into targeted athleticmovements. Unaware of this distinction, some strength and conditioning professionals advise athletes and clients to perform what they call "sport-specific exercises" or "functional exercises" by attaching a resistance band to the end of a golf club or hockey stick, for example, or shadow-boxing against bands strapped around the back. Loading specific sport skills in this manner misapplies the principle of specificity and rests on a misunderstanding of how to properly use specific exercises.
In reality, improving one's ability to perform certain sport skills is not about replicating what a specific movement looks like but about replicating the specific force-generation patterns involved in the movement pattern. In other words, when training focuses only on what an exercise looks like, one can easily make the mistake of loading sport-specific skills instead of working to improve the specific force-generation patterns used to perform sport movements.
The problem lies in the fact that sport movement skills involve accuracy components that are not just similar but exact. For example, consider studies of the use of weighted bats in baseball. Contrary to general public understanding, studies have found that the heavy bat not only alters the batter's perceptions of bat heaviness and swing speed, but also slows the batter's swing speed for as many as five swings after using the weighted bat (2,3)! Sure, some baseball players might prefer to "warm-up" by using a weighted bat, but the smart ones will also take several more swings with an unweighted bat to normalize themselves before stepping up to the plate.
You can test this effect for yourself: Shoot 10 free throws with a regular basketball, then take 10 more shots with a 2-to 4-pound (1 to 2 kg) medicine ball. You'll quickly find that the fine-motor pattern (i.e., skill) used to throw the heavier ball accurately is completely different, and your shots with that ball will likely come up short until you hone the pattern. After shooting with the medicine ball, go back to the normal basketball for 10 more shots. Your first few shots may go over the backboard because shooting the much lighter basketball involves a different fine-motor sequence than shooting the medicine ball.
Learn more about Building Muscle and Performance.