Functional training is the utilization of exercises which involve complex, multi-joint movements of the upper body, core and lower body. These movements enable greater overall bodily functioning and performance enhancement through improved coordination and the proper stimulation of muscular firing patterns. This type of training is more than just training the body for life movements, it is preparing the body to be able to react and function better and more efficiently in any environment or situation.
Functional training involves exercise that is both efficient and effective. Effective means that it works to improve both form and function. Efficient means that there is no wasted effort, it works and is free of wasted or useless effort. For example, in performing an efficient and effective squat, there must be minimal joint risk and maximum range of motion with an up-down tempo and direction of movement from standing position to the bio-mechanical limitations at the end range. Functional exercise works because it focuses on involving the muscles that are used daily, and their integrated functions during increasingly complex movements. It only works if the exercises are successful in activating the muscles being used for the exercise in the order and sequence needed.
By definition functional training is training with purpose. In other words it should have a positive effect on the activity or sport one is participating in. It should involve multi-faceted and integrated approaches to improving strength and overall conditioning for anyone who uses it. Originally this functional approach was exclusive to the rehabilitation and sports medicine field. Work hardening is a modern approach used by physical therapists for rehabilitation. This is a type of sports specific conditioning for every day life which teaches the patient how to lift boxes, turn wrenches, carry beams, push wheel barrels, or anything else that is applicable to their work and functional environment. This is the true definition or explanation of functional exercising. Every person must perform some physical labor or task, usually either lifting, pushing or pulling an object.
Functional training must integrate all the aspects of human movement. To get a better understanding of the approach needed, one must first become a student of human movement. Observing children at play, adults at work, and athletes performing a training session should reflect this reality to some extent. The truth is however, that almost any exercise can be functional for someone at a specific time in his or her life or training cycle. Often times if one is at the early stages of rehabilitation, or just starting training, then the use of selectorized machines or simple exercise movements may be needed and considered functional given the circumstances.
However in general, the use of machines as a way to challenge someone and add "resistance" to any particular movement, goes against this philosophy of functional training for many reasons. Today the training movement tends to emphasize wobble boards, bosu ball, medicine balls, stability balls, bands and body weight exercises. Originally this type of equipment was used in a rehabilitation setting to enhance static balance, proprioception, joint stability and core strength.
The important thing however is to first understand the needs and abilities of the individual before implementing those techniques and strategies. Companies often sell training equipment as a way for strength coaches, personal trainers, and athletes to enhance performance and add variety to a training program. The use of this equipment has lead many people to believe that it is an essential part of functional training. Just because an exercise is challenging does not mean that it is necessarily functional. Unstable equipment is only one modality that should be used sparingly at best.