2 2 Lesson 9.1 Objectives Describe the functions of muscles.Describe the functions of muscles. List the three types of muscles.List the three types of muscles. Describe the types of skeletal muscle fiber.Describe the types of skeletal muscle fiber.
4 4 Muscles and Force Muscle can change chemical energy (from ATP) into mechanical energyMuscle can change chemical energy (from ATP) into mechanical energy –Energy: the capacity to do work When muscle contracts, muscle tissue transforms one form of energy into another and it is able to produce forceWhen muscle contracts, muscle tissue transforms one form of energy into another and it is able to produce force 2 Types of force2 Types of force –Dynamic force: creates movement and change –Static force: expends energy, but creates no movement or noticeable change (like pushing against a wall) (like pushing against a wall)
10 IsometricIsometric –Tension in the muscle with no change in movement IsotonicIsotonic –Concentric –Eccentric From Greenstein GM: Clinical assessment of neuromusculoskeletal disorders, St. Louis, 1997, Mosby. Muscle Action
Specific Disorders, VI Shin splintsShin splints –Inflammation or tearing of the muscle from the tibia, usually tibialis anterior, can also result in stress fractures Anterior compartment syndromeAnterior compartment syndrome –Any condition that increases pressure in the compartment of the leg can cut off blood supply and nerve function –Overuse, repetitive stress and accelerated growth are common factors Plantar fasciitisPlantar fasciitis –Inflammation and slight tearing of the plantar fascia –Caused by excessive stress to the foot commonly near the attachment to the clacaneus (stress causes calcium deposits, which can cause bone spurs) FibromyalgiaFibromyalgia –Aching, fatigue, stiffness, sleep disruption, multiple tender points, headaches, irritable bladder, dysmenorrhea, cold sensitivity, restless leg, Raynauds Phenomenon, numbness, tingling, and weakness Acquired metabolic and toxic myopathiesAcquired metabolic and toxic myopathies –Nutritional and vitamin deficiency, especially protein and vitamin C, D. E, may lead to myopathy