Elastic Performance
The Speed Key: The Stretch-Shortening Cycle (SSC)
When we talk about elite sprinting performance, one of the most important physiological mechanisms at work isn’t just muscle action — it’s tendons at play here too. This natural function allows athletes to store, release, and redirect elastic energy, creating fast efficient movement.
At its core, the SSC consists of three phases:
Eccentric phase – the muscle lengthens under load (think: foot striking the ground).
Amortization phase – a very brief pause — the faster this transition, the better.
Concentric phase – the muscle “rebounds” or shortens to propel you forward.
This cycle is a spring-like mechanism — a compressing and releasing coil — enhancing the efficiency and execution of sprinting. This quality can have a profound impact on sprint performance, therefore your in game performance, matches, or competitions.
Why the SSC Matters for Sprinting Performance
In sprinting, every ground contact is the SSC in action. During each step:
Muscles & tendons lengthen quickly as you intitate braking force (eccentric, ground contact)
Elastic tissues — especially tendons — store energy that energy
That stored energy is then rapidly released to drive the concentric push-off.
Tissue can adapt accordingly through proper training to enable a more compliant structure.
The result… Shorter & Efficient Ground Contact Time | Higher Force Output | Higher Braking Forces | Faster Sprint Times.
Youth Development: Fueling Speed
The ability to use the SSC efficiently doesn’t emerge fully formed. It primarily develops over childhood and adolescence as the body grows and matures. Key changes include:
🧠 Neuromuscular Development
Better motor unit recruitment and timing.
Enhanced pre-activation of muscles before ground contact.
Improved stretch reflex contribution for faster force production.
Together, these improve how quickly and effectively muscles react
🦾 Structural Growth
Muscle size and fascicle length increase, enabling stronger and faster force generation.
Tendon stiffness and size grow, enhancing elastic energy storage and return.
Muscle architectural changes improve rate of force development.
These collectively boost SSC performance as kids mature into adults creating lasting effects.
Mitigating Injury with Higher Exposures
Here’s where things get especially important for coaches and parents: the same structures that make you faster also protect you from injury.
A well-developed SSC system:
Improves braking force efficiency during high-impact landings and direction changes.
Reduces ground contact time, raising the bodies tolerance to high speed forces
Encourages balanced strength between muscles and tendons, which creates a harmonic evironment for effective performance
If children don’t develop a robust SSC during growth, they may be at higher risk for issues like overuse injuries, muscle strains, or tendon overload as demands increase in their sport.
Support SSC Growth: Practical Performance Tips
Although biology has a say in how these systems mature, training plays a powerful role in accelerating SSC proficiency and preparing young athletes for the demands of sprinting.
🔹 Movement variety
Encourage hopping, skipping, and playful jumping
🔹 Bounce A lot
Teach athletes to redirect force explosively. Quality is crucial: safe landing mechanics and gradual progression matter most.
🔹 Get Strong
Strength training builds resilience and supports tendon health, lowering injury risk.
🔹 Coaching and Cueing
Coaching, programs, and drills that elicit SSC adaptation properly and safely
SSC: Speed Key
The stretch-shortening cycle is far more than a buzzword — it’s a foundational mechanism of human movement. If the goal is better sprint performance and healthier athletic development, we must support the growth and maturation of this mechanism.
For young athletes, this isn’t just about running faster today — it’s about building systems that are repeatable, effective, and result oriented over time.
