Thank goodness the body can compensate. Here is a perfect example of this discussed in this study.
“ … it has been shown that a fatigued muscle decreases the body’s ability to attenuate shock from running. The purpose of the study was to determine the effect of lower extremity fatigue on shock attenuation and joint mechanics during a single-leg drop landing.”
This study suggests that as one part fatigued, the joint and muscle strategies elsewhere in the limb made up for it.
“Hip and knee flexion increased and ankle plantarflexion decreased at touchdown with fatigue. Hip joint work increased and ankle work decreased.” The results suggested that the lower extremity is able to adapt to fatigue though altering kinematics at impact and redistributing work to larger proximal muscles.
The effect of lower extremity fatigue on shock attenuation during single-leg landing. Clin Biomech (Bristol, Avon). 2006 Dec;21(10):1090-7. Epub 2006 Sep 1.
Coventry E1, O'Connor KM, Hart BA, Earl JE, Ebersole KT.