Types Of Musclular Contractions + Muscle Fibre Types

Question 1

Isometric contractions

Answer 1

The muscle generates force without changing its length
Example
- Plank

Question 2

Isotonic Contractions
Name both types

Answer 2

The muscle length changes whilst maintaining constant tension

• Concentric
• Eccentric

Question 3

Concentric Contraction

Answer 3

The muscle contracts / gets shorter as it generates force
Example
- Bicep curl when bringing the weight towards the shoulder

Question 4

Eccentric Contraction

Answer 4

The muscle lengthens whilst generating force
Example
- RDL

Question 5

Isokinetic Contractions

Answer 5

The muscle contracts at a constant speed throughout the movement
The force that is produced is the same throughout the movement
Requires specialist equipment to achive
Example
- ACL rehab machine (Roy Keane video)

Question 6

Muscle Fibre types
Name all

Answer 6

Type 1
Type 11a
Type 11x

Question 7

Type 1

Answer 7

Contraction Speed: Slow
Force Production: Low
Fatigue Resistance: High
Energy System: Aerobic (oxidative metabolism)
Mitochondria & Capillary Density: High (for oxygen supply)
Myoglobin Content: High (appears red in color)
Endurance Activities
- Marathon
- Ironman

Question 8

Type 11a

Answer 8

Contraction Speed: Fast
Force Production: Moderate to High
Fatigue Resistance: Moderate
Energy System: Uses both aerobic and anaerobic metabolism
Mitochondria & Capillary Density: Moderate
Myoglobin Content: Moderate (pinkish appearance)
Moderate intensity activities
- Football
- 400m

Question 9

Type 11x

Answer 9

Contraction Speed: Very fast
Force Production: High
Fatigue Resistance: Low
Energy System: Anaerobic (glycolysis, phosphocreatine system)
Mitochondria & Capillary Density: Low
Myoglobin Content: Low (appears white in color)
Explosive activities
- 100m sprint
- Weightlifting

Question 10

Myoglobin

Answer 10

The greater the myoglobin content the greater the ability for endurance activities
Function
- Oxegen storage
- Aerobic energy production