The specificity of training principle is sometimes referred to by the acronym SAID (specific adaptation to imposed demands). In a nutshell, it states that you get better at the things you train for.
If you regularly do bicep curls, you will get better at curling; but you won’t automatically become better at climbing trees. This training principle seems like common sense, but don’t dismiss it too hastily. It is important that you understand how the specificity inherent in your lifting program relates to your everyday activity.
The specificity of training principle and your bulking routine
If specificity of training didn’t exist, we could all train the same way no matter what our goals were. There would be no such thing as bulking routines, agility training, speed training, or general purpose fitness training.
Instead, we have to figure out what it is we’re trying to accomplish, then design an exercise program that is specifically tailored to that goal.
For skinny guys who want to bulk up and add muscle mass, the lifting program has to be specific to that goal. It must build strength throughout the entire body – the muscles, tendons, and ligaments – without being specific to any particular sport or lifestyle. In short, you want a general-purpose bulking workout rather than a bodybuilding program or sports-specific training regimen. Later, after you have a solid base of strength, you may want to tailor your training to a more specific goal like sports training or muscle symmetry.
Specificity dictates the equipment you use to bulk up
In a lot of fitness and health centers, most of the people strength train using machines. This is convenient for the management but less than ideal for the patrons. Machines lock you into an extremely specific movement pattern while simultaneously reducing or removing the need for balance, spinal stabilization, and the development of synergistic muscle groups.
Strength training with free weights is a different story. Free weight routines that are suitable for novices or guys who want to bulk up are, by their very nature, less specific and more general in nature. As such, they are better for overall fitness. With free-weight compound exercises, you are training movements rather than individual muscles. Your balance will improve and you will develop your body as a whole rather than as a collection of unrelated parts.
When you perform a lift using a machine, you are inadvertently engaging in specificity training. Your workout suffers because of it. The skills you learn and the strength you develop will have much less carry-over to your everyday activities than if you had used free weights.
Compound lifts for bulking up
To add muscle mass, use compound lifts. If you are a novice or a casual lifter who is interested in size and strength, you may prefer lifts like the squat, deadlift, overhead press, bench press, and pull up. However, if you are already in fairly good shape and you want to develop your athleticism, you might benefit from learning the Olympic lifts: the clean and jerk, the snatch, the overhead press, and the related assistance lifts.
Whatever your preference, the lessons we learn from the specificity principle show that isolation movements are anathema to novice lifters who want to add significant muscle mass.