Running and Sport

Question 1

What is the main purpose of running shoes

Answer 1

• Protection/reduction of high-pressure areas on foot
• Pressure = force/area (spread out force)
• Reduce impact peak and loading rate of ground reaction forces
• Improve stability and control

Question 2

Overpronation/ motion control

Answer 2

Combined frontal and transverse plane rotation
- led to the development of motion control shoes: Goal is to control and limit the amount of pronation occurring during running
- Pronation is an important mechanism of the foot
- Overpronation does not lead to injuries
- severe or extended pronation may still be an issue

Question 3

Anatomy of a Running Shoe

Answer 3

UPPER
- Foot support and heel stabilizing
MIDSOLE
- where most of the science happens
- Shock absorption stability motion control
OUTSOLE
- Rubber sole for traction and durability

Question 4

Midsole thickness

Answer 4

Aimed at absorbing impacts and reducing rate of ground reaction forces

Question 5

Midsole Stiffness

Answer 5

Improved stability and/or running performance

Question 6

Nike Vaporfly 4% (2017)

Answer 6

• Said to give runners an efficiency edge of 4.2% over other shoes
• Marketing campaign tied to a 2-hour marathon
• ZoomX foam: extra-think (31mm), but light weight, compliant and resilient (85% energy return)
• Carbon fiber plate: stiffer midsole that acts like a lever or spring

Question 7

Argument for barefoot running

Answer 7

Said to improve proprioception and strength of foot, ultimately leading to improved stability and control and reduce impact forces

Question 8

Barefoot running changes in gait

Answer 8

Complex interaction between foot strike, cadence and impact forces
- 10% reductions in stride length can lead to a 5% reduction in joint forces
- rearfoot strike patterns have longer stride lengths than mid- or forefoot strike patterns
- Running without cushion pushes people away from a rearfoot strike pattern

Question 9

Does barefoot running reduce injuries

Answer 9

• One study followed 100 barefoot and 100 shod runners for a year
• BF more foot/ankle injuries
• SH more hip/knee injuries
• Injury rate higher in BF but total injuries higher in shod - more people run with shoes

Question 10

Key differences between shod and barefoot running

Answer 10

SHOD
- Rear foot strike
- impact peak/load taken up more by knee
- more likely to have knee pain
BAREFOOT
- Mid/forefoot strike
- Impact peak/load is taken up more by the foot/ankle
- More likely to have foot or Achilles tendon pain

Question 11

Take home points of running gait analysis and injury reduction

Answer 11

• Different movement patterns will always exist and trying to correct may not be warranted (especially if there is no pain)
• Simply finding a comfortable shoe and managing training load may be the most important factors

Question 12

Inertial sensors and impact peak measurement

Answer 12

Impacts often measured as the vertical or resultant peak of the tibia