chapter 4 lecture building muscular strength & endurance

Chapter 4 Lecture

Building Muscular Strength

& Endurance

© 2013 Pearson Education, Inc.

Learning Outcomes

• Explain how muscular strength and muscular endurance relate to lifelong fitness and wellness.

• Identify key skeletal muscle structures and explain how they work together to allow for basic muscle function.

• Articulate the fitness and wellness improvements you can make with regular resistance training.

• Evaluate your changes in muscle fitness over time by assessing your muscular strength and muscular endurance at regular intervals.

© 2013 Pearson Education, Inc.

Learning Outcomes continued

• Set and work toward appropriate muscular fitness goals

• Implement a safe and effective resistance training exercise program compatible with your goals and lifestyle.

• Observe safety precautions when resistance training.

• Incorporate strategies to avoid the risks associated with supplement use.

© 2013 Pearson Education, Inc.

Terms

• Muscular fitness– The ability of your musculoskeletal system to perform daily and

recreational activities without undue fatigue

• Muscular strength – The ability of a muscle or group of muscles to contract with maximal force

• Muscular endurance– The ability of a muscle to contract repeatedly over an extended period of

time

• Resistance training (weight training) – Putting measured stress on the musculoskeletal system, resulting in

greater strength and endurance

© 2013 Pearson Education, Inc.

How Do My Muscles Work?

• Three basic muscle types:

– Skeletal muscle (voluntary)• Allows movement and generates body heat

– Cardiac muscle (involuntary)• Exists only in the heart; helps pump blood

– Smooth muscle (involuntary)• Lines internal organs and moves food

© 2013 Pearson Education, Inc.

How Do My Muscles Work? continued

• Skeletal muscle consists of:– Tendons (connective tissue)– Muscle fibers (individual muscle cells)– Myofibrils (strands containing protein filaments)

• Two types of muscle fibers:

– Slow-twitch: oxygen dependent; contract slowly but for longer periods without fatigue

– Fast-twitch: not oxygen dependent; contract faster but tire more quickly

© 2013 Pearson Education, Inc.

Parts of a Muscle

© 2013 Pearson Education, Inc.

Motor Units and Muscle Contraction Strength

© 2013 Pearson Education, Inc.

How Do My Muscles Work? continued

• Three primary types of muscle contraction:

– Isotonic (consistent muscle tension)• Concentric• Eccentric

– Isometric (consistent muscle lengthening)

– Isokinetic (consistent muscle contraction speed)

© 2013 Pearson Education, Inc.

Isotonic and Isometric Contractions

© 2013 Pearson Education, Inc.

How Can Resistance Training Improve My Fitness and Wellness?

• Regular resistance training…

– Increases strength• Neural improvements• Muscle size

– Increases muscular endurance

– Improves body composition, weight management, and body image

© 2013 Pearson Education, Inc.

How Can Resistance Training Improve My Fitness and Wellness? continued

• Regular resistance training…

– Strengthens bones and protects against injury

– Helps maintain functioning with aging

– Reduces cardiovascular disease risk

– Enhances sports performance

© 2013 Pearson Education, Inc.

Physiological Changes from Resistance Training

© 2013 Pearson Education, Inc.

Age-Related Muscle Loss

© 2013 Pearson Education, Inc.

How Can I Assess My Muscular Strength and Endurance?

• 1 RM (repetition maximum) tests– The most common strength measurement tool– Must get medical clearance to lift weights– Use Lab 5.1 to get started

• Grip strength test– Also a common muscular strength measurement– Uses a grip strength dynamometer (equipment)

© 2013 Pearson Education, Inc.

How Can I Assess My Muscular Strength and Endurance? continued

• 20 RM (repetition maximum) tests– Can use any weight-training exercise– Useful for setting endurance goals– Use Lab 5.2 to get started

• Calisthenic tests– Conditioning exercises using body weight– Sit-ups, curl-ups, pull-ups, push-ups, etc.– Use Lab 5.2 to get started

© 2013 Pearson Education, Inc.

How Can I Design My Own Resistance-Training Program?

• Set appropriate muscular fitness goals.

– Use SMART goal guidelines• Specific, measurable, action-oriented, realistic,

time-based

– Appearance-based goals• Be sure to include ways to measure progress.• Be wary of unrealistic expectations.

– Function-based goals• Include specific goals for function increases.

© 2013 Pearson Education, Inc.

How Can I Design My Own Resistance-Training Program? continued

• Explore your equipment options.

– Machines

– Free Weights

– Alternate Equipment • Resistance bands, etc.

– No-Equipment Training • Calisthenics, e.g.

© 2013 Pearson Education, Inc.

Machine-Weight vs. Free-Weight Training

© 2013 Pearson Education, Inc.

How Can I Design My Own Resistance-Training Program? continued

• Understand the different types of resistance-training programs.

– Traditional weight training• Uses sets and repetitions• Circuit weight training: relies on principle of specificity

– Plyometrics and sports training• Used more by athletes than by casual exercisers• Plyometrics mimic quick, explosive sport actions• Power lifting• Speed and agility drills

– Whole-body exercise programs

© 2013 Pearson Education, Inc.

How Can I Design My Own Resistance-Training Program? continued

• Learn and apply FITT principles:

– Frequency• How often you train each week

– Intensity• Resistance• Overload

– Time• Number of sets and repetitions per session

– Type• Selecting appropriate exercises

© 2013 Pearson Education, Inc.

Guidelines for Resistance Training

© 2013 Pearson Education, Inc.

Repetitions vs. Resistance

© 2013 Pearson Education, Inc.

Fitness Flowchart

© 2013 Pearson Education, Inc.

Muscle Anatomy

© 2013 Pearson Education, Inc.

How Can I Design My Own Resistance-Training Program? continued

• What if you don't reach your goals?

– Track your progress.• Use a log or journal.• Lab 4.4 can help you get started.

– Evaluate and redesign your program as needed.• Good times to revisit the program include:

– Target completion date

– When you feel you're not progressing

– When you experience overtraining fatigue or injury

© 2013 Pearson Education, Inc.

What Precautions Should I Take to AvoidResistance-Training Injuries?

• Follow basic weight-training guidelines.– Start conservatively.– Follow the "10 percent rule."– Proceed gradually.

• Be sure to warm up and cool down properly.– Include both general and specific warm-ups.– Include light stretching.

© 2013 Pearson Education, Inc.

What Precautions Should I Take to AvoidResistance-Training Injuries? continued

• Know how to train with weights safely.– Use a spotter.– Move slowly and with control.

• Get advice from a qualified exercise professional.– Look for certified, experienced trainers.

• Persons with disabilities may have different weight-training guidelines.– These will vary for different individuals and needs.– Get medical clearance.– Locate reputable resources for information.

© 2013 Pearson Education, Inc.

Is It Risky to Use Supplements for Muscular Fitness?

• Ergogenic aids – Dietary supplements marketed as promoting muscle

conditioning (also called performance aids)– Unproven for safety and effectiveness– Can include controlled substances such as anabolic

steroids

• Anabolic steroids– Synthetic drugs related to testosterone– Sometimes used illegally for performance enhancement– Induce serious negative side effects

© 2013 Pearson Education, Inc.

The Mitchell Report on Steroids in Baseball

• Why is this the "steroid era" of professional baseball?• Why do you think Major League Baseball did not

confront the use of steroids by players before the Mitchell Report was released?

• Why do you think no punishment was imposed on the players who used steroids? Do you agree with this position?

• What are the effects of steroid use by professional athletes on young people and fans?

© 2013 Pearson Education, Inc.

Is It Risky to Use Supplements for Muscular Fitness? continued

• Creatine – Legal supplement containing amino acids– Should be taken only at recommended levels– Few side effects reported, but long-term effects

unknown

• Adrenal androgens (DHEA, androstenedione)– The body's most common hormone– Acts as a weak steroid– No proof of safety or effectiveness– Can cause serious side effects

© 2013 Pearson Education, Inc.

Is It Risky to Use Supplements for Muscular Fitness? continued

• Growth hormone (GH)– Produced naturally by pituitary gland– Produced synthetically for medical use– Serious side effects of illegal use include irreversible

bone growth, cardiovascular disease risks, and reduced sexual capacity

• Amino acid and protein supplements– Used in hopes of enhancing muscle development– Evidence of effectiveness is mixed– Large doses can create imbalances and are dangerous

to people with liver/kidney disease