This document provides an overview of the muscular system including: 1) Types of muscle such as cardiac, smooth, and skeletal muscle which makes up 40% of total body mass. 2) The microscopic structure of skeletal muscle including sarcomeres which contain actin and myosin filaments responsible for muscle contraction. 3) The sliding filament theory of muscle contraction involving interactions between actin, myosin, calcium, and ATP. 4) How nerve impulses trigger muscle contraction through the process of excitation-contraction coupling. 5) Causes of muscle fatigue including reduced ATP, lactic acid buildup, dehydration, and decreased nerve signals.

1. Applied Exercise Physiology Section 5: Body Systems Topic 1: Muscular System Prepared by Mr. Cerny Niagara Wheatfield Senior High School

5. Actin & Myosin

9. Sarcoplasmic Reticulum

18. Muscle Types nonoxidative Few Sprinting /bursts No Few Fast Same (slightly more) Fast twitch (II) Oxidative Many Endurance Yes Many Slow Same (slightly less) Slow twitch (I) Oxidative / nonoxidative # capillaries Activity Resistance to fatigue # mit. Speed Force