Expose to Graded Demands
Expose to Graded Demands
When we talk about graded demand, what we’re really after is finding the sweet spot, the right “entry point” that allows adaptation without exceeding the tissue’s current capacity for stress. The goal? Increase tolerance without tipping into irritation.
Most are familiar with the Envelope of Function (Scot Dye model), but another valuable framework is the Physical Stress Theory (PST). PST gives us a more nuanced lens by emphasizing that stress is a composite— not just how much load we apply, but how long and in what way it’s applied.
According to PST, tissues respond to stress in five ways:
- Decreased tolerance
- Maintenance
- Increased tolerance
- Injury
- Death
These aren’t just endpoints. They’re signals. And PST tells us that stress isn’t just about how much—it’s also how long and in what direction.
Stress = a composite of:
- Magnitude (how much)
- Time (how long or how fast)
- Direction (tension, compression, shear, torsion)
Injury typically results from one of three combinations:
- High magnitude, short duration – e.g., a hamstring strain during high-speed sprinting
- Low magnitude, repeated exposure – e.g., Iliotibial Band Syndrome in endurance runners
- Moderate-to-high magnitude, repeated exposure without adequate recovery – e.g., stress fractures from cumulative bony loading in distance running or military rucking
The key insight: The poison is also the antidote. Adaptation lives in the dosage. By understanding the underlying stress variables, we gain clarity in how to titrate load—across magnitude, time, and direction—with more precision.
-Jarred