Center of Mass, Stability and Mobility

Question 1

What is the Center of Mass?

Answer 1

A point where the mass of the body is evenly distributed

Question 2

How can COM be changed?

Answer 2

Change of body shape

Movement of limbs

Question 3

What is the line of gravity?

Answer 3

Passes through the COM

Represents the direction gravity acts on the body

Question 4

How is equilibrium achieved?

Answer 4

When the line of gravity passes through the Base of Support

Question 5

What is stability?

Answer 5

Where the body resists being moved

Question 6

What is mobility?

Answer 6

Quality of movement readily from one place to another

Question 7

Does less stable mean more or less mobile?

Answer 7

More

Question 8

What are the 4 factors that affect stability?

Answer 8

1. Area of base of support
2. Height of COM
3. Line of gravity in relation to base of support
4. Mass of performer

Question 9

What is the height in relation to percentage of the body for females and males?

Answer 9

Males COM= 56-57% of standing height

Females COM= <55% of standing height

Question 10

Why is the COM lower in females?

Answer 10

Due to the wider pelvic angle

Question 11

When accelerating what happens to the BOS, COM and Position of Line of gravity?

Answer 11

BOS: Decreases
COM: Raises
Position of line of gravity: Ahead (leaning foward to begin)

Question 12

When stopping what happens to the Line of gravity

CM and BOS

Answer 12

Line of gravity: Behind (Lean back to stop)
CM: Lowered
BOS: Increased