Physiological changes of training
Testing - Evaluation
Strength training concepts
Return to function - Core Muscles Muscle Physiology
Force of Contraction
Physiologic changes of training
Skeletal Muscle Structure
Mitochondria produce energy ATP
Sarcolemma muscle fibers membrane
Sarcomere contractile unit of skeletal muscle.
Myofibril are small units of striated muscle fibers that contain contractile myofilaments actin and myosin. Consist of successive sarcomeres Myoglobin protein inside muscle fibers that releases O2
Tropomyosin and troponin are an important to the actin helix, preventing permanent bonding of the myosin cross-bridge to actin Troponin a regulatory protein associated with tropomyosin, causes change in orientation of actin filament, by binding with Ca++ ion Sacroplasmic reticulum surrounds each myofibril and stores Ca++ at rest Motor Unit
Motor nerve and all the muscle fibers that it attaches to
Neuromusclar junction area between the nerve cell and the muscle fibers it innervates (motor end plate) one per muscle cell Small muscles (fine movement) require small number of motor units When stimulated all the fibers will contract
Extrafusal - impulses from brain cause chemical reaction producing a collapse of cross-bridges allowing actin and myosin to slide - Contraction Intrafusal - muscle spindles information changes in length and tension. Reflex action in response to a stretch on a muscle, a stronger contraction to reduce the stretch Muscle Contraction
Action potential - electrical current to the muscle fibers (sarcolemma) Release of acetylcholine causes excitation of the sarcolemma (Baechle 94) Intercellular Ca++ increase - bonds with troponin-tropomyosin releases inhibition Change in orientation of actin filament...