10.5 Running

Question 1

What defines running compared to walking?

Answer 1

Running has a longer swing phase, shorter stance phase, and two flight phases with no ground contact.

Question 2

How many flight phases occur during running, and when?

Answer 2

Two: at the start of initial swing and end of terminal swing.

Question 3

How does the body move in running vs. walking?

Answer 3

Walking: COM moves like an inverted pendulum. Running: COM moves like a bouncing ball/pogo stick using elastic recoil.

Question 4

What happens to step length, velocity, and cadence when transitioning from walking to running?

Answer 4

All increase, while step duration decreases.

Question 5

How do ground reaction forces change from walking to running?

Answer 5

They increase significantly in running.

Question 6

What provides forward momentum in walking vs. running?

Answer 6

Walking: momentum from stance phase. Running: momentum from arm and leg movement during swing.

Question 7

What are the two main phases of the running gait cycle?

Answer 7

Stance phase and swing phase.

Question 8

What are the subdivisions of the stance phase in running?

Answer 8

Absorption and propulsion.

Question 9

What are the subdivisions of the swing phase in running?

Answer 9

Initial swing and terminal swing.

Question 10

What happens during the absorption phase of running?

Answer 10

From initial contact to midstance, muscles eccentrically absorb impact forces.

Question 11

What happens during the propulsion phase of running?

Answer 11

The heel lifts off, and gastroc and soleus propel the body forward.

Question 12

When does the first double float phase occur in running?

Answer 12

At the beginning of initial swing.

Question 13

When does the second double float phase occur in running?

Answer 13

At the end of terminal swing.

Question 14

How does increased running speed affect stance and swing time?

Answer 14

Stance time decreases, swing time increases.

Question 15

What happens to the center of mass (COM) as running speed increases?

Answer 15

The COM lowers, and the trunk leans forward.

Question 16

What changes occur at the pelvis during faster running?

Answer 16

Anterior pelvic tilt increases with speed.

Question 17

How does hip motion differ between walking and running?

Answer 17

Hip extension occurs later (at toe-off) in running, and flexion increases during swing for foot clearance.

Question 18

When does the hip reach maximum flexion during running?

Answer 18

At the beginning of terminal swing.

Question 19

How much does the knee flex during absorption in running?

Answer 19

About 45°.

Question 20

What is the maximum knee flexion during midswing in running?

Answer 20

About 90–130°.

Question 21

Does the knee reach full extension during propulsion?

Answer 21

No — it extends to about 20° but not fully.

Question 22

When does the ankle reach maximum dorsiflexion during running?

Answer 22

Just before midstance (~20° dorsiflexion).

Question 23

What motion does the ankle perform during propulsion?

Answer 23

Plantarflexion for push-off.

Question 24

What type of foot strike commonly occurs during running?

Answer 24

Posterolateral or midfoot strike.

Question 25

How does stride and cadence change with faster running?

Answer 25

Stride lengthens, cadence increases, and stance time shortens.

Question 26

What happens to joint range of motion as speed increases?

Answer 26

ROM increases at the hip, knee, and ankle.

Question 27

When is muscle activity greatest during running?

Answer 27

After initial contact (absorption), during propulsion, and at terminal swing.

Question 28

How does muscle activation differ between walking and running?

Answer 28

Muscle activity in running is earlier and more intense.

Question 29

Which muscles produce most of the power for running?

Answer 29

Hip flexors, extensors, abductors, knee extensors, and gastroc-soleus.

Question 30

What muscles are key for propulsion in late swing and early stance?

Answer 30

Hip extensors.

Question 31

What muscles accelerate the leg during swing after toe-off?

Answer 31

Hip flexors.

Question 32

Which muscles support the body during stance?

Answer 32

Quadriceps, gluteus medius, and plantarflexors.

Question 33

How much greater are impact forces in running vs. walking?

Answer 33

Running = 2–3× body weight, walking = 1.3–1.5× body weight.

Question 34

What does the ground reaction force (GRF) curve look like in running?

Answer 34

A double bump pattern — small impact peak followed by a larger propulsion peak.

Question 35

When does the larger GRF peak occur during running?

Answer 35

During the propulsion phase of stance.

Question 36

Why is the propulsion peak greater than the impact peak in running?

Answer 36

More force is needed to push off than to absorb impact.

Question 37

Clinically, what demands make running distinct from walking?

Answer 37

Greater joint ROM, eccentric control, and propulsive power.

Question 38

What are common injury sites due to running’s high demands?

Answer 38

Knee, hip, ankle, and Achilles tendon.

Question 39

What should therapists assess in running mechanics?

Answer 39

Stride pattern, COM control, cadence, and impact absorption.