Muscular Fitness

Muscular Fitness Sports Medicine: Physical Fitness

Bellwork • List the physical demands of the sport assigned to your group by your teacher. • Be prepared to share your answers with the class.

Objectives • 1. Define new vocabulary terms • 2. Review muscular anatomy • 3. Differentiate between muscular strength and muscular endurance • 4. Distinguish between various types of muscle contractions

Terminology: • Muscular fitness – a term used to refer to muscular strength and muscular endurance • Strength – the ability to exert force • Endurance – the ability to contract a muscle repeatedly or hold a contraction for a long period of time • Hypertrophy – an increase in the size of muscle cells • Atrophy – a decrease in the size of muscle cells • Progressive resistance- a gradual increase in the amount of weight applied to the muscles • Overload – subjecting the body’s systems to loads greater than what they are used to

Terminology (cont.) • Isometric– a muscle contraction with little or no movement occurring • Isotonic – a muscle contraction with movement occurring, usually lengthening and shortening • Isokinetic – a muscle contraction where maximum resistance is applied and speed is kept constant through a full range of motion • Concentric – a contraction where muscles shorten • Eccentric – a contraction where muscles lengthen

Terminology (cont.) • Set – a given number of repetitions • Repetition – a complete muscle contraction

Review of Muscle Types • 1. Skeletal – attached to bones and allow voluntary movements* • 2. Smooth – line the walls of organs (ie, stomach, blood vessels); involuntary • 3. Cardiac – make up the walls of the heart; involuntary • *Type involved in muscular strength and endurance

Review of Muscle Fibers • Fibers – the long, thin cells that make up muscles

Review of Muscle Fibers • Type of muscle fibers determine strength & endurance • A. Slow-twitch fibers: red in color, contract at a slow rate. These fibers are involved in cardiovascular activities such as running. • B. Fast-twitch fibers: white in color; contract quickly. These fibers are important for strength activities. • C. Intermediate muscle fibers: have characteristics of both slow- and fast-twitch fibers. They contract quickly and have good endurance.

Review of Muscle Fibers

Review of Muscle Fibers (cont.) • Individual’s muscle fibers are genetically determined, but can be improved through training • Weight training results in hypertrophy (increase in the size of muscle cells) • Inactivity results in atrophy (decrease in the size of muscle cells)

Weight Training • Exercises done to improve muscular strength and endurance • Based on principles of progressive resistance and overload • Performed with machines or free weights • Uses repetitions and sets

To increase strength, which of these variables would you increase? Which would you decrease? # of Repetitions? Amount of Resistance? # of Sets? Length of recovery period? 2 PROPERTY OF PIMA COUNTY JTED, 2010

Methods for Increasing Strength 1. Decrease the number of repetitions • 2. Increase the amount of resistance • 3. Increase the number of sets • 4. Decrease the recovery period or rest intervals between sets

Benefits of Increased Strength • Ability to perform ADL’s (activities of daily living) more efficiently with less fatigue • Prevent health problems • Strengthen bones – reduced risk of osteoporosis • Prevent muscle injuries and muscle soreness • Helps maintain weight by burning more calories than fat • Help maintain good posture

To increase endurance, which of these variables would you increase? Which would you decrease? # of Repetitions? Amount of Resistance? # of Sets? Length of recovery period? 2 PROPERTY OF PIMA COUNTY JTED, 2010

Methods for Increasing Endurance • Decrease the amount of resistance • Increase the number of repetitions • Increase the number of sets • Increase the recovery period or rest intervals between sets

Benefits of Increased Muscle Endurance • Able to work longer without getting tired • Able to maintain good posture • Less likely to have low back problems, muscle soreness and injuries • Increased lean body mass / decreased fat • Look and feel better • Good bone strength • Reduced risk of cardiovascular disease

Check your knowledge • True or False? • Increased lean muscle mass and decreased body fat are benefits of muscular endurance? • Performing ADLs with more efficiency and increased fatigue are benefits of muscular strength.

FITT Formula for Muscle Fitness

Isometric Contraction • A muscle contraction with little or no movement occurring • +requires little or no equipment • +builds posture muscles that have to contract for long periods during the day • - boring/difficult to be motivated

Isotonic Contraction • A muscle contraction with movement, usually lengthening and shortening • +same resistance through ROM • +measurable results • + high motivation • - equipment required

Isokinetic Contraction • A muscle contraction where the speed is kept constant and maximum resistance is applied through a full range of motion • + constant speed (↑power) • + constant resistance • + safety • - expense of machine • - don’t allow eccentric contractions

Which Is Correct?(hold up fingers) Type of contraction with constant speed ? • Isotonic contraction • Isometric contraction • Isokinetic contraction 24 PROPERTY OF PIMA COUNTY JTED, 2010

Which Is Correct?(hold up fingers) Type of contraction with constant resistance? • Isotonic contraction • Isometric contraction • Isokinetic contraction 25 PROPERTY OF PIMA COUNTY JTED, 2010

Which Is Correct?(hold up fingers) Requires expensive equipment? • Isotonic contraction • Isometric contraction • Isokinetic contraction 26 PROPERTY OF PIMA COUNTY JTED, 2010

Which Is Correct?(hold up fingers) Easy to measure results? • Isotonic contraction • Isometric contraction • Isokinetic contraction 27 PROPERTY OF PIMA COUNTY JTED, 2010

Letter or Note to a Friend Write a note to a friend or absent classmate explaining the learning 28 PROPERTY OF PIMA COUNTY JTED, 2010

Muscular Fitness