Transcript Chapter 8
Chapter 8 Muscular Analysis of Upper Extremity Exercises Muscular Balance Contralateral Assessment 10-15% difference Agonist to Antagonist Ratio Anterior to Posterior Development Activity Analysis Concepts Muscles are usually grouped (aggregate) according to their concentric function (agonists) and work in paired opposition to an antagonistic muscle group. Elbow Flexion Shouler Extension Supination Cooperative Teamwork Agonists: • Concentric contraction Antagonists: • Lengthening without tension: • Lengthening under tension: Kinetic Chain Concept Body Extremities – Several bony segments linked by a series of joints. These are likened unto a linkage system of a chain. Open Kinetic Chain Chain: Distal end of the extremity is NOT fixed to any surface • Core of body and proximal segment are stabilized • Any joint in the extremity can move or function separately without causing movement in other joints of the extremity. • Allow you to isolate a particular joint (muscle or muscle group) • Sheer forces and distractive forces are acting on the joint Closed Kinetic Chain: Chain Distal end of the extremity is fixed • Movement of one joint causes predictable movement in other joints of the extremity. • Involves several joints and muscle groups – how most activity occurs • Joint is more stable due to compressive forces from weight bearing. Analysis of Movement 1. Analyze movement of each involved joint by individual movement phase 2. Determine which muscles are performing the movement 3. Know what type of muscle contraction is occurring 4. Understand role of antagonists, synergists, stabilizers, neutralizers, etc. 5. Know exercises to strengthen and stretch the involved muscles Click for movie Click for movie Movement Phases Stance Phase Preparatory Phase (cocking or wind-up) Summation of force – near maximal concentric muscle activity of involved muscles Follow-Through Phase (deceleration) Place the involved muscles in stretch position in preparation for concentric muscle contraction Movement Phase (acceleration or action) Balanced body position from which to initiate skill/movement Relatively static phase accomplished through isometric contractions Begins immediately following climax of movement phase Eccentric muscle contraction of antagonistic muscles to movement Recovery Phase Regain balance and positioning Muscles used to eccentrically decelarate movement essentially used concentrically to initiate return to normal position Baseball Pitch Movement Phases Lifting Phase: concentric contraction overcoming resistance, causing movement Lowering Phase: eccentric contraction controlling resistance Dips Bench Press Pull up