Controllable Factors (2)

Question 1

What are six essential characteristics of a running shoe?

Answer 1

1. Attenuation of single / multiple impact forces
2. Preservation of foot stability (rearfoot control)
3. Adequate friction / traction
4. Provision of different footstrike type
5. Heat dissipation
6. Comfort

Question 2

What does ‘Uppers’ refer too in a running shoe?

Answer 2

A compound structure (foam layer-nylon-cotton weave)

Question 3

What does ‘Midsoles and Wedges’ refer too in a running shoe?

Answer 3

Shock absorption parts of the shoe, made from closed-cells polymeric foam (EVA) which contain gas or liquid.

Durability: –30% after 500 miles

Question 4

What does ‘Outsoles’ refer too in a running shoe?

Answer 4

Durable and abrasion-resistant polyurethane rubbers.

Treading increases the traction, especially under wet conditions

Question 5

What does ‘Insole board’ refer too in a running shoe?

Answer 5

A fibre-board that provides the rigid base for the rest of the shoe

Question 6

What does ‘Insole’ refer too in a running shoe?

Answer 6

Contributes to the reduction of impact forces, perspiration absorption and comfort

Question 7

What does ‘Heel counter’ refer too in a running shoe?

Answer 7

Provides rear-foot stability and claimed to prevent excessive pronation (hard or high heel tabs may cause tendon inflammation).

Question 8

What does ‘Inserts’ refer too in a running shoe?

Answer 8

These help to reduce impact and increase rear-foot stability

Question 9

What is the energy absorption by each different part of the shoe?

Answer 9

60% midsole-wedge
20% outsole
10% insole
3% insole board
2% sock.

Question 10

Barefoot running (Fact Card)

Answer 10

Barefoot running has become more popular due to claims that its more natural state results in better foot movements and fewer injuries.

It is true that running barefoot tends to lead to different running techniques like initial contact typically made on the forefoot rather than the heel but this in itself could lead to injury because of increased loading on the calf muscles.

The forefoot landing technique is beneficial in running (and is the predominant technique used in sprinting) because of increased use of the stretch shortening cycle, but many recreational runners are physically unprepared for this activity of the muscle-tendon unit.

Question 11

What is Friction?

Answer 11

The locking of surfaces

Question 12

What is Traction?

Answer 12

The interlocking of surfaces

Question 13

What is compliance?

Answer 13

The opposite of stiffness

Question 14

Low compliance results in what?

Answer 14

High risk of injury

Question 15

High compliance results in what?

Answer 15

Low risk of injury

Question 16

What is resilience?

Answer 16

The amount of energy returned as a percentage of the amount of energy absorbed at impact

Question 17

What is hardness?

Answer 17

Resistance to penetration

Question 18

What is impact attenuation?

Answer 18

Measurement of reduction of impact forces

% of reduction of the max impact force on a surface x compared with that generated on concrete

Question 19

Why are surfaces such as sand harder to run on?

Answer 19

Running on sand had a greater energy cost than running on grass and proposed that this was because of a reduction in elastic energy potentiation, caused partly by an increase in contact time (and thus a longer delay between the eccentric and concentric actions of the lower limb muscles).

They also suggested that the increase in energy cost could be because sand’s compliant nature requires increased leg stiffness that requires increased muscle activity to stabilise the lower limb joints

Question 20

Artificial surfaces

Answer 20

Non-compliant surfaces: higher impact characteristics (related to cartilage/bone damage and lower back pain). Asphalt, concrete and wood are the worst.

Synthetic surfaces: if stiff lead to joint and tendon injuries.

Suggested running surfaces: grass, dirt paths and wood chips.

Artificial surfaces do not allow the same degree of sliding as natural ones and they also resist rotation.

200% higher incidence of tennis related injuries on artificial (non-sliding) surfaces than natural (sliding) surfaces.