Mechanical, Neuromuscular and Metabolic Specificity...

Mechanical specificity refers to the movements and the weight placed on the body. For example, to develop muscular endurance use lighter weights (but not too light since lifting too easy will result in a virtual waste of time) and high repetitions. To develop maximal strength use heavier weights (while always maintaining proper form).

Neuromuscular specificity refers to the speed of the contraction and the exercise selected. For example, to develop higher levels of stability while pushing, chest exercises must be performed with controlled, unstable exercises at slower speeds. This would require lying on a stability ball rather than lying on a standard bench (this variation is for more intermediate to advanced individuals, but with time, practice and diligence, you can get there safely). In order to develop higher levels of strength, these exercises must be performed in a more stable environment with heavier weights to emphasize prime moving muscles. In order to develop higher levels of power, you must use lower weights, with higher velocity contractions which must performed in a plyometric fashion (exercises which generate quick, powerful movements such as utilizing a forceful soccer ball throw).

Metabolic specificity refers to the energy demand placed on the body. In order to develop endurance the training must include longer bouts of exercise with very little rest between sets. This type of training uses aerobic pathways (requiring oxygen) to supply energy for the body. In order to develop maximal strength and power, training will require longer rest periods so that the intensity of each bout of exercise will remain high. Energy will now be supplied mostly through anaerobic pathways (oxygen not required).

***Mechanically, the body burns more calories when exercises are performed while standing and using moderate weights. 

***From a neuromuscular standpoint, the body burns more calories when more muscles are used for longer periods in controlled, unstable environments.

***Metabolically, the body burns more calories when rest periods are short in order to minimize full recuperation. This would include weight-lifting exercises performed in a circuit fashion with virtually no rest in between sets.

Stay tuned for specific exercises to illustrate all of the above!