Exercise Sciences Flashcards
What are the different roles of slow-twitch versus fast-twitch muscle fibres?
Slow-twitch : endurance activities like running, cycling, or holding a position for a long time
Fast-twitch : quick, powerful movements like sprinting, jumping, or lifting heavy weights
How do slow-twitch muscle fibres versus fast-twitch work?
Slow-twitch : they contract slowly and don’t produce a lot of force, but they can keep going for a long time without getting tired
Fast-twitch : they contract quickly and generate a lot of force but get tired faster because they rely on energy systems that don’t need oxygen.
What are the different fuel sources of slow-twitch versus fast-twitch muscle fibres?
Slow-twitch : they primarily use oxygen (aerobic energy system) to produce energy
Fast-twitch : primarily use the glycolytic system (a system that doesn’t use oxygen)
What are the types of muscle fibres and are they slow-twitch or fast-twitch?
Type I : slow
Type IIa : fast (mix between endurance and power)
Type IIx : fast (most explosive fibres that fatigue very quickly)
What factors influence the distribution of slow versus fast-twitch muscle fibres between individuals?
Genetics : the proportion is largely determined by genetics.
Is recovery quicker in slow-twitch muscle fibres or fast-twitch? Why?
Slow-twitch because they rely on aerobic metabolism which doesn’t create as many byproducts like lactic acid which can hinder recovery.
What are the 3 cardinal planes of movement?
1-sagittal plane
2-coronal or frontal plane
3-transverse plane
What are the movements allowed in the sagittal plane? Give examples.
Flexion and extension. Movements that involve moving forward or backward.
For example, squats (flexion and extension of the hips and knees), running (forward motion of the legs), bicep curls (flexion and extension of the elbow).
What are the movements allowed in the coronal or frontal plane? Give examples.
Abduction and adduction. Movements in the frontal plane occur side to side.
For example, lateral raises (abduction of the arms), side lunges (side-to-side motion of the legs), jumping jacks (arms and legs moving away from the body, abduction).
What are the movements allowed in the transverse plane? Give examples.
Rotation. Movements involve rotational or twisting motions.
For example, rotational exercises (Russian twists), golf swings (rotation of the torso), throwing motions (rotation of the shoulders).
What are the 3 different axes of rotation? And where do they pass?
1-sagittal axis : pass horizontally from posterior to anterior and is formed by the intersection of the sagittal and transverse planes
2-frontal axis : pass horizontally from left to right and is formed by the intersection of the frontal and transverse planes
3-vertical axis : pass vertically from inferior to superior and is formed by the intersection of the sagittal and frontal planes
Explain the movement of extension.
Extension is a movement that increases the angle between two body parts. To put it simply, imagine straightening a bent joint. For example:
- If you start with your arm bent at the elbow and then straighten it out, that’s an extension of the elbow.
- Standing up straight after being in a crouched position is extending the knees and hips.
Explain the movement of flexion.
Flexion is a movement that decreases the angle between two body parts. In simpler terms, it’s like bending a joint. Here are a few examples:
- When you bend your elbow to bring your hand towards your shoulder, that’s flexion of the elbow.
- When you bend your knee to bring your heel towards your buttocks, that’s flexion of the knee.
Explain the movements of abduction and adduction.
Abduction and adduction refer to movements of the limbs or body parts relative to the midline of the body.
Abduction : when a body part moves away from the center of the body. For example, a shoulder lateral raise
Adduction : when a body part moves back toward the center of the body. For example, bring your legs back together from a spread position
Explain the movement of rotation.
The movement of a body part around its own axis.
For example, when you turn your head to look over your shoulder, that’s rotation of the neck. When you rotate your arm in a circular motion, that’s rotation of the shoulder.
