Chapter 3 - Strength

Question 1

Two characteristics of Muscle strength

Answer 1

1. Muscles ability to exert Max force

2. The amount tension a contracting muscle can produce

Question 2

Definition of Endurance

Answer 2

Muscles ability to sustain a sub max force

Question 3

Muscle Strength Definition

Answer 3

The ability for a muscle to produce tension and the resulting force outcome during max effort in a dynamically or statically position in relations to the demands of force.

Question 4

What is power?

What is the equation for power?

Answer 4

Power is strength and speed: work per unit of time

Strength = (force)(displacement) over (time)

Question 5

Main factors of strength?

Answer 5

1. Cross sectional sizes of muscles
2. Recruitment of motor units
3. Muscle length tension relationship
4. Type of muscle contraction
5. Muscle fiber type distribution
6. Speed of contraction
7. Motivation and other psychological factors

Question 6

Characteristics of muscle fiber Type 1
Contract speed?
Conduct speed? 
Color?
Fatigue? 
Activity? Mitochondria?

Answer 6

Characteristic: Oxidative
Mitochondria: Greater number; characteristic: Oxidative
Activity: Endurance
Fatigue: Greatest
Color: Red
Conduct speed: Slow (small axon size) Contract speed: (Slowest)

Question 7

Characteristic of Type 2 Fiber?
Contract speed?
Conduct speed?
Color?
Fatigue?
Activity? Mitochondria?

Answer 7

Mitochondria: Smaller numbers; Characteristic: Glycolytic 
Activity: Brief burst
Fatigue: least 
Color: White 
Conduct Speed: Fast (larger axon sizes) 
Contract Speed: Fast

Question 8

Why does the length-tension relationship have the greatest amount of strength?

Answer 8

• Actin slide over myosin
• In order to achieve max strength there must be enough myosin to pull in actin towards the center of the sacromere (optimal use of myosin and actin)
• If sacomere too stretched there is not enough cross bridges to be formed. Develops less tension
• if too contracted then too mucho overlap. Myosin are crumpled together