Weight lifting causes a profound affect on bones and muscles. These structures get stronger and bigger as a result of the stresses placed on them. In addition to these morphological adaptations to exercise, the components of the nervous system also benefit from regular training with weights, which results in improved motor skills. The term motor skills collectively describe neurological functions such as balance, coordination, motor unit recruitment and proprioception.
Balance
Balance, defined as your ability to maintain your center of gravity within your base of support, develops by performing exercises in the standing position. Squats, lunges, standing shoulder press and step ups are all good examples of exercises that require and develop balance. You can adapt exercises to make them more balance-specific by standing on one leg, exercising one arm at a time, closing your eyes or performing exercises using a balance ball. Balance is especially important if you play nonlinear sports such as football, basketball, soccer or hockey.
Coordination
Your ability to move multiple limbs in a smooth and harmonious fashion is called coordination, for example, running while simultaneously reaching above your head to catch a ball. Multi-planar movements such as lunges with a twist or squats with an overhead press will help to develop your coordination. To emphasize coordination, try combining a variety of exercises into one smooth movement: perform a dead lift followed by a power clean followed by a front squat followed by an over-head press followed by a back squat. This sequence -- called a complex -- would then be repeated from the beginning and performed for three to five laps.
Proprioception
Proprioception describes your innate sense of the position of your limbs, despite the fact they may be out of view. Sometimes called muscle sense or kinesthetic sense, proprioception is vital in many weight-lifting exercises: for example, your ability to keep your spine correctly aligned even though you cannot see your back. Proprioception is an important part in many sports and is especially challenged when running on uneven surfaces or responding to stimuli that are not in your immediate view; for example, blocking a blow to the side of your head when boxing.
Strength
Although the development of strength is mainly morphological, motors skills play an important part. Strength training improves both the condition of your muscles and the nerves supplying them. The fibers in your muscles are arranged in groups called motor units and each motor unit is controlled by a single motor nerve. The more motor units you can recruit at the same time, the greater the amount of force you can develop. Beginner exercisers may only be able to "switch on" 60 percent of their muscle's motor units, whereas a more advanced lifter recruits 90 percent or more, demonstrating much greater strength. This is why some seemingly slightly built people are stronger than those that are more heavily muscled.
Speed and Power
Speed describes your ability to move quickly, whereas power is your ability to generate maximum force at speed. Both of these physical characteristics are the result of highly developed motor skills and are essential ingredients in many sports. Both speed and power are the result of a well-tuned nervous system and highly developed motor skills. Your ability to generate maximum speed and power depends on your ability to recruit multiple motor units at the same time and at a very rapid rate. Multiple motor units must "fire" in sync to generate maximal force in minimal time. Exercises such as squat jumps, power cleans and push presses will develop your speed and power.
References
- "Strength Ball Training: Full Range of Stability and Medicine Ball Exercises"; Lorne Goldenberg and Peter Twist; 2006
- "Essentials of Strength Training and Conditioning"; National Strength and Conditioning Association; 2008
- "Principles of Anatomy and Physiology"; Gerard J. Tortora and Bryan H. Derrickson; 2008
