Fatigue-related firing of muscle nociceptors reduces voluntary activation of ipsilateral but not contralateral lower limb muscles.

Abstract in brief

• Fatigue-related firing of muscle nociceptors decreases voluntary activation in the same leg's muscles but does not affect the opposite leg, indicating limited crossover of fatigue effects between limbs.
• Experimental results show that maintaining muscle afferent firing through ischemia during fatiguing exercises reduces voluntary muscle activation in the fatigued limb, but not in the contralateral limb.
• These findings suggest that group IIIIV muscle afferents play a role in limiting muscle activation within the same limb during fatigue, but this mechanism does not contribute to central fatigue affecting both limbs.