Axial Training refers to working out the muscles proximal to the spine, pelvic and shoulder girdles. Examples of some muscles would be Trapezius, Erector Spinae, Hamstrings, Glutes, Quadriceps, etc. Some examples of exercises would be Clean & Jerk, Squat, Power Clean, Deadlift, Bent-over Row, Good Morning, Squats, etc.Peripheral Training refers to training the muscles acting on the joints that are farther from the spine. Examples of some muscles would be Biceps, Triceps, Forearms, lower leg muscles, etc. Some examples of exercises would be Leg extension, Hammer curls, Bicep Curls, Calf exercises, etc.
The advantages of axial training are increased capacity for prolonged and powerful work, respiratory rate increases, causes the sympathetic system to adapt, condition the joints and muscles, and conditions the neuromuscular system.The advantages of peripheral training are does not require peak cardiac power output, allows people to train longer at lower intensities, and stimulates elements of the central cardiovascular and pulmonary system.
The disadvantages of axial training are the exercises are more technically challenging and require weeks or months to properly learn the motor patterns and are more physically demanding.The disadvantages of peripheral training are postural deformities, resorting to machines, which predisposes people to more injuries, hinders the reactive response of the heart and lungs, and development of inflexible limbs.
Clearly it is easy to see why axial training is far superior to peripheral training, however peripheral training should be used to some extent to condition the limbs to bear heavy loads.If a trainee were to spend more time squatting and less time curling or using the pec deck machine, the trainee would increase strength/mass more and feel better about their progress.