The second issue of AEM exclusive Fitness Training articles will concentrate on the importance and benefits of Strength Training. Strength training consists of overloading a particular muscle or muscle groups to the point of fatigue. Adaptations occur within the muscles that experience the overload. Changes occur in the size, strength, type, enzyme activity and fiber recruitment within the muscle. To fully understand the adaptations of strength training you must firstly understand a brief anatomy and function of muscles.
Muscle Structure
A muscle contains thousands of small hair like structures called muscle fibers. They run the entire length of the muscle and connect to tendons, which in turn are connected to bones. When a muscle contracts the muscle fibers shorten pulling on the tendon and causing movement to occur in a joint. Muscular contractions are controlled by nerve impulses that are sent from the brain.
Muscle Fibers
There are 2 major types of muscle fibers, each have very different characteristics. Every muscle in the body is comprised of both muscle fiber types. The first type of muscle fiber is a Type I fiber, this fiber has high endurance and low power characteristics. In contrast, Type II fibers are high power but have low endurance. ATV racing uses both types of fibers.
Muscle Contractions
There are 3 types of muscular contractions: isometric, concentric and eccentric. Isometric contractions occur when there is force produced in the muscle yet no movement takes place, an example would be in the leg muscles and arms when pushing against an immovable object. An concentric contraction is when the muscle shortens as it develops tension, as seen in your bicep muscles when curling a dumbbell. During an eccentric contraction the muscle lengthens as it develops tension, an example of this would be lowering a dumbbell following a bicep curl, even though you are lowering the weight your bicep will still feel firm and under tension. |
