WORKOUT
UNDER FATIGUE
How to build strength to maintain efficient running mechanics
– with Jurgens Grobler
WHY YOU FALL APART LATE IN A RUN
You don’ t lose speed because you’ re unfit. You lose it because you can’ t maintain efficient running mechanics under fatigue.
Early in a run, everything feels controlled:
• Cadence is consistent
• Stride feels elastic
• Movement feels effortless
Then it shifts. Posture starts to drop. Ground contact becomes heavier. Stride length shortens.
You’ re still working just as hard, but you’ re moving less efficiently.
That’ s not just fatigue.
That’ s your ability to maintain movement quality under fatigue starting to break down.
WHAT’ S ACTUALLY HAPPENING?
As fatigue builds, several key changes occur:
• Force production decreases
• Ground contact time increases
• Lower limb stiffness reduces
• Movement becomes less coordinated
This leads to a drop in running economy, meaning you use more energy to maintain the same pace.
You may also notice:
• Reduced knee drive
• Increased overstriding
• Loss of trunk stability
Individually, these are small changes. Together, they are what slow you down.
THE REAL LIMITER
Most runners train:
• Speed when fresh
• Endurance at lower intensities
But they neglect the most important skill: Maintaining efficient mechanics under fatigue.
Because performance isn’ t just about how fast you can run. It’ s about how well you can hold your form when fatigue is highest.
THE TRAINING SHIFT
To improve this, training must reflect the demands of racing. Instead of separating strength and running, we combine them:
• Pre-fatigue the system with strength work
• Transition directly into running
• Repeat under controlled fatigue
This approach improves:
• Neuromuscular control
• Force production under fatigue
• Running economy in a fatigued state
40 www. modernathlete. co. za