This is a summary from a section in my upcoming speed development...
Fred Duncan@Fred__Duncan
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Jul 21, 2025
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This is a summary from a section in my upcoming speed development e-book, which also includes a full training program.
“Stiffness” is one of the most common terms in performance training and one of the most misunderstood. It gets thrown around without much context, and
“Stiffness” is one of the most common terms in performance training and one of the most misunderstood. It gets thrown around without much context, and
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that’s where the confusion starts.
In sprinting, we often talk about ankle and knee stiffness because those joints need to briefly yield, attenuate/produce force and rebound rapidly. But the question I get a lot is, does this apply beyond sprinting?
Yes, stiffness
In sprinting, we often talk about ankle and knee stiffness because those joints need to briefly yield, attenuate/produce force and rebound rapidly. But the question I get a lot is, does this apply beyond sprinting?
Yes, stiffness
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matters in change of direction, lateral movement, and most field-based actions.
•In a hard cut, ankle stiffness helps control foot placement and avoid collapse through the arch
•Knee stiffness helps maintain alignment and tolerate eccentric load
•Without it,
•In a hard cut, ankle stiffness helps control foot placement and avoid collapse through the arch
•Knee stiffness helps maintain alignment and tolerate eccentric load
•Without it,
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athletes lose time and stability in the transition from deceleration to reacceleration
Of course, stiffness without timing or rhythm doesn’t help much. This is where understanding the type of stiffness you’re training and the means you’re using really matters.
Of course, stiffness without timing or rhythm doesn’t help much. This is where understanding the type of stiffness you’re training and the means you’re using really matters.
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•Plyometrics → improve muscle stiffness
•Heavy strength work and isometrics → improve tendon stiffness
•Joint stiffness is developed through control, positioning, and co-contractions
Good programming doesn’t chase one adaptation, it targets the ones that actually
•Heavy strength work and isometrics → improve tendon stiffness
•Joint stiffness is developed through control, positioning, and co-contractions
Good programming doesn’t chase one adaptation, it targets the ones that actually
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support the athlete’s movement and goals. That means addressing all of it.
I offer custom remote coaching for athletes worldwide My preset speed programs, beginner, advanced, and youth, are all on sale as I wrap up my new sprint system
fredduncantraining.com
I offer custom remote coaching for athletes worldwide My preset speed programs, beginner, advanced, and youth, are all on sale as I wrap up my new sprint system
fredduncantraining.com