Health and Wellness

Muscular Strength and Endurance

Chapter 4

 

 

Terminology Review:

 

1. Muscular Strength – The amount of force a muscle can produce with a single maximum effort.

 

2. Muscular Endurance – The ability of a muscle or group of muscles to remain contracted (sustain a level of muscular force or to contract repeatedly.

 

3. Muscle fiber - A single muscle cell, usually classified according to strength, speed of contraction, and energy source.

 

4. Myofibrils - Protein structures that make up muscle fibers.

 

.     5.   Hypertrophy - Increase in the size of muscle fiber, usually stimulated by muscular overload.

 

5. Atrophy- A decrease in the size of muscle cells.

 

6. Hyperplasia- An increase in the number of muscle cells

 

      7.   Slow-twitch fibers - Red muscle fibers that are fatigue-resistant but have a slow contraction

     speed and a lower capacity for tension; usually recruited for endurance activities.

 

       8.  Fast-twitch fibers - White muscle fibers that contract rapidly and forcefully but fatigue

           quickly; usually recruited for actions requiring strength and power.

 

       9.  Power - The ability to exert force rapidly.

 

      10. Motor unit - A motor nerve (nerve that initiates movement) connected to one or more

       muscle fibers.

 

11. Tendon- a tough band of fibrous tissue that connects a muscle to a bone or other body part

      and transmits the force exerted by the muscle.

 

      12. Ligament - A tough band of tissue that connects the ends of bones to other bones or supports

     organs in place.

 

      13.  Testosterone - The principal male hormone, responsible for the development of secondary

      sexual characteristics and important in the increase of muscle size.

 

      14. RM (repetitions maximum) - the maximum amount of resistance that can be moved a specified

     number of times; 1 RM is the maximum weight that can be lifted once.

 

15. Repetitions - The number of times an exercise is done during one set

 

16. Isometric (static) - The application of force without movement; also called static.

 

      17. Isotonic (dynamic) - The application of force resulting in movement; also called dynamic.

 

18. Concentric contraction - An isotonic contraction in which the muscle gets shorter as it

       shortens.

 

19. Eccentric contraction - An isotonic contraction in which the muscle lengthens as it

       contracts.

 

20. Eccentric (pilometric) loading – Loading the muscle while it is lengthening; sometimes called negatives.

 

21. Plyometrics- rapid stretching of a muscle group that is undergoing eccentric stress (the muscle is exerting force while it lengthens), followed by a rapid concentric contraction.

 

22. Speed Loading- moving a load as rapidly as possible.

 

23. Isokinetic- The application of force at a constant speed against an equal force.

 

      24. Spotter - A person who assists with a weight training exercise done with free weights. 

 

      25. Set- a group of repetitions followed by a rest period.

 

      26. Agonist- a muscle in a state of contraction, opposed by the action of another muscle, its antagonist.

 

      27. Antagonist- A muscle that opposes the action of another muscle, its agonist.

 

 

Study Questions:

 

 

1.  What are some of the benefits of muscular strength and endurance?

 

2.  How do increased muscular strength and endurance prevent the occurrence of injuries?

 

3.  How does strength training improve your body composition?

 

4.  How is self-image affected by weight training?

 

5.  What is muscular strength, and how does it differ from muscular endurance?

 

6.  How do muscles increase in size as a result of weight training?

 

7.  What are fast-twitch and slow-twitch muscle fibers?

 

8.  What are some of the physiological changes and benefits of weight training?

 

9.  What is the difference between isotonic and isometric weight training?

 

10.  What are the advantages and disadvantages of exercise machines and free weights?