Specificity really has its roots in the area of motor learning. The Theory of Specificity of Motor Learning suggests that for motor skills to carry over outside of the practice environment, learning and development of the skills must resemble the environment that the motor skills are to be used in outside of the practice environment. In the exercise realm, this theory has been broadened to include the same concept in that for carry over to occur, training must resemble competing.
So, why is this such a complicated concept? Well, for one, there are by some accounts about 86 billion neurons in the brain. For strength and conditioning training to carry-over to the competitive environment, in some meaningful way some of these 86 billion neurons must turn-on in pathways replicated in both environments. Think about this for a minute, that’s a lot of specifics to account for.
The likelihood of robust transfer from the weight room to the competition environment is actually probably small the way most athletes train and would requires a better effort to understand the context in which muscular strength is used during competition, which is a lot differently than doing a squat or bench press. The same goes for conditioning exercises in that in sport there's generally a lot more going on then just running from point A to point B. Unless practice reflects this, then we can expect little transfer. In this regard, classical work: rest ratios are probably less effective than most of us think as well as how we much we have minimized the value of maintaining a base level of conditioning. Lack of conditioning actually may be more of a factor for sports injuries than lack of strength, in my opinion.
The term specificity also denotes there are many different variables at play that link a relationship to practice (training) and competing. Some of these include physiology, motor-learning, muscular applications, conditioning applications, movement patterns (skill), experience (learning factors/confidence), excitability, external factors, stress, and hardiness. This list could be increased. Also, its important to note that these variables relate specifically to the context in how they are used or stressed (situational development). It is within this understanding that specificity has more value to both clinicians and athletes.
A bottom line is that we have to move beyond the logic of “competitive sports movements are explosive and therefore performing explosive exercises during training will make athletes more explosive during competing.” Granted, there’s a lot of tradition in this logic, but I’m going to tell you a secret, its logic that missing the mark of specificity. Again, it's not just an explosive movement that's the key as many of us have been lead to believe, but how this variable (explosiveness) is used in a contextual nature. Here's where we have to do better in understanding applications of training transfer. Without this, unfortunately, one simply trains to train. Nice, but for athletes its probably a waste of time.
Does this mean that we give up on training the body? Heck no, but we should have a better idea of why we're doing what we're doing. Some of the benefits of muscular fitness include developing the strength of muscles and connective tissue and to help increase lean muscle mass. Some of the benefits of conditioning exercise are to help promote cardio-vascular fitness and to hardy energy system pathways. However, again, both aspects of strength and conditioning have to be viewed within the context of how they're applied outside of training. We should first try and better understand competing, generate prediction models for training, train an athlete, analyze outcomes, adapt and adjust training, and then compete. This is a continuum, not an end in and of itself.
Realize there are limitations with specificity of training in that if we don't try and make some sense of the competition variables, we can't very well predict how to best train over a period of time within each athletic population. In conjunction, we should also look at the value of developing aspects of correctness of training skill execution and leadership development as other variables that may have carry-over potential.