Physiology of strength training
Download
1 / 43

5230strength1 - PowerPoint PPT Presentation


  • 280 Views
  • Uploaded on

Physiology of Strength Training Part 1 – Muscle Function Skeletal Muscle Anatomy 660 muscles Approximately 45% of body weight 75% water, 20% protein (12% myofibullar and 8% enzymes, etc) 5% inorganic salts Largest organ system End organ for the primary support systems involved in exercise

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about '5230strength1' - Audrey


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Physiology of strength training l.jpg

Physiology of Strength Training

Part 1 – Muscle Function


Skeletal muscle anatomy l.jpg
Skeletal Muscle Anatomy

  • 660 muscles

  • Approximately 45% of body weight

    • 75% water, 20% protein (12% myofibullar and 8% enzymes, etc) 5% inorganic salts

  • Largest organ system

  • End organ for the primary support systems involved in exercise


Skeletal muscle anatomy3 l.jpg
Skeletal Muscle Anatomy

  • Basement membrane – outer most ‘membrane’

  • Plasma membrane or sarcolemma

  • Satellite cells – between membranes

    • growth, development, adaptation

    • under stress they are responsible for hypertrophy and hyperplasia

  • Multi-nuclei

    • 200-300 nuclei per millimeter

      • 85-95% within the scaroplasm

      • 5-15% in the basement membrane

    • Tremendous potential for gene alterations


Skeletal muscle anatomy4 l.jpg
Skeletal Muscle Anatomy

  • Muscle

  • Fascicle

  • Fibers


Skeletal muscle structure l.jpg
Skeletal Muscle Structure

  • Epimysium, Endomysium, and Perimysium converge to form tendons and are very elastic


Skeletal muscle anatomy6 l.jpg
Skeletal Muscle Anatomy

  • Muscle

  • Fascicle

  • Fibers

  • Myofibrils

  • Myofilaments

    • Actin

    • Myosin






Skeletal muscle anatomy13 l.jpg
Skeletal Muscle Anatomy

  • What are the three proteins that make up actin?

  • Actin, tropomyosin, and troponin

  • What is the function of actin?

  • What is the function of tropomyosin?

  • What is the function of tropoin?



Skeletal muscle anatomy15 l.jpg
Skeletal Muscle Anatomy

  • Myosin is also referred to as the thick myofilament

  • Myosin heads

  • What does myosin use its heads for?


Skeletal muscle anatomy16 l.jpg
Skeletal Muscle Anatomy

  • Myosin

  • Actin

  • M-line proteins

  • Titin/Nebulin


Muscle strength l.jpg
Muscle Strength

  • Where is the strength of a muscle generated?

  • Muscle strength comes from the interaction of myosin and active

  • How is the strength of a muscle generated?


Muscle contraction generating force l.jpg
Muscle Contraction:Generating Force

  • Stimulation

  • Calcium

  • Actin/Myosin

  • Sliding

  • Energy/ATP



Motor unit l.jpg
Motor Unit

  • What is a motor unit?

  • One motor nerve

  • All the muscle fibers (cells) that it stimulates

  • Example. 1:4

  • Actual MU range from 1:10s to 1:1000s


Neuromuscular junction l.jpg
Neuromuscular Junction

  • How does a nerve stimulate a muscle fiber?

  • Neurotransmitter substance

  • Acetylcholine (ACh)


Neuromuscular junction23 l.jpg
Neuromuscular Junction

  • Acetylcholine (acetate and choline)

    • Reuptake of choline

    • Fatigue?

    • Supplement?


Depolarization and action potential l.jpg
Depolarization and Action Potential

  • Acetycholine

  • Sodium gates open

    • Depolarization

  • Action Potential

  • Propagation of Action Potential

  • Sarcolemma

  • T-tubules


Muscle contraction calcium l.jpg
Muscle Contraction: Calcium

  • After the T-tubule, where does the action potential go?

  • What is stored in the sarcoplasmic recticulum?

  • Where does the calcium go?

  • FYI: Too much lactic acid may block Ca release.


Muscle contraction actin myosin l.jpg
Muscle Contraction: Actin/Myosin

  • Ca binds to troponin

  • Troponin causes tropomyosin to shift or move

  • This uncovers the active sites on the actin.

  • Once uncovered, the myosin heads will attach to the active site


Muscle contraction sliding l.jpg
Muscle Contraction: Sliding

  • What does the myosin head do once it attaches?

  • This is called a power stroke.

  • What happens to the actin?

  • The myosin breaks away, reattaches, power stroke…

  • In this case, what happens to the sarcomere?


Slide32 l.jpg

Actin and Myosin Interaction

Charged myosin head and covered active sites.

1.

2.

Uncovered active site; myosin head attaches.

3.

Power stroke sliding actin inward; myosin head uncharged.

4

ATP separates and recharges myosin head.


Muscle contraction energy l.jpg
Muscle Contraction: Energy

  • What is ATP?

  • What does it provide?


Slide34 l.jpg

ADP + P

Energized

ADP + P + energy

New

ATP


Muscle relaxation l.jpg
Muscle Relaxation

  • What is needed in order to have the muscle stop contracting?

  • Stop the impluse

  • Re-store the calcium

  • How? Calcium pump

  • What powers the calcium pump?


Summary of muscle contraction l.jpg
Summary of Muscle Contraction

1. Motor Impulse

2. Neurotransmitter Substance

3. Action potential via Na and K

4. Calcium released exposing active sites

5. ATP split forming high energy myosin


Summary of muscle contraction37 l.jpg
Summary of Muscle Contraction

6. Myosin attaches to actin forming a crossbridge

7. Stored energy released and crossbridge movement (Power Stroke)

8. ATP breaks myosin from actin

9. ATP splits forming high energy myosin


Quick time movie l.jpg
Quick Time Movie

  • Yellow = Calcium

  • Green = ATP

  • Gray = ATPase

  • A Quick Time Movie of the contraction process can be download at the 5230 Web Page


Muscle strength43 l.jpg
Muscle Strength

  • So far…

  • ...Where and how is the strength of a muscle generated?

  • Next…

  • ….What makes a muscle stronger?

    • Acute increase

    • Chronic increase


ad