Reactivity

Reactiveness is the amount of displacement an athlete can achieve utilizing momentum with a ground contact of less than 250ms. 

The Level of Reactivity greatly impacts an athletes change in direction ability.

• Stacked with Cocked Ankle
• Ball of the foot contact in the Power Position
• Pre-activation.
• Crisp! Reactive Ground Contact. We only have 250ms. Think fast, like lightening.
• Explosive Law of Flow. Make sure you complete the impulse. Full hip extension.
• Direction of Force Application.
• No Deformation. (Law of Lines)

Cues of Reactivity

• Too Slow- takes longer than 250ms.
• Too Much Joint Range- during force absorption
• Poor Impulse. Insufficient impulse
• Line Violation. Especially dynamic valgus, thoracic collapse and foot collapse
• No pre-activation.
• Thud Noise vs crisp reactive ground contact
• Poor Foot Contact- not cocked, landing on toes and too much ankle range of motion
  

Common Problems

Develop Pre-Activation

Develop Motor Control of Pre-activation. Appropriately challenge the system.

Long Term Athletic Development. 

Learn the reactive stacked position (Plyometrics, Olympic Lifting)

Reactive Impulse Development [HIP]

via Full Spectrum Training. How quickly can you apply force and the direction of force application in the stacked reactive position.

Develop Elasticity 

Develop the Foot Power Position

Injury Management and Load Management

Determinants of Reactiviteness

Force Absorption

- eccentric phase

Force Utilization

-amortization phase

Force Production

-concentric phase

Stretch Shortening Cycle

Spring like mechanism

1. Force Absorption -think compressing a spring

2. Force Utilization  - as short ground contact as possible

3. Force Production- think releasing the spring