Heavy-resistance exercise-induced increases in jump performance are not explained by changes in neuromuscular...

Area of Science:

• Neurology
• Sports Science
• Exercise Physiology

Background:

• Post-activation potentiation (PAP) is theorized to enhance explosive muscular performance after intense exercise.
• Evidence linking PAP to improvements in whole-body explosive performance (PE) following heavy-resistance exercise is inconsistent.
• Neuromuscular adaptations are proposed mechanisms for PAP, but require further investigation.

Purpose of the Study:

• To investigate the neuromuscular basis of explosive performance enhancement (PE) after heavy-resistance exercise.
• To determine if post-activation potentiation (PAP) underlies improvements in PE.
• To assess changes in corticospinal excitability and muscle activation post-exercise.

Main Methods:

• Eleven male athletes underwent heavy-resistance exercise.
• Measures included countermovement jump (CMJ) performance, transcranial magnetic stimulation (TMS) for corticospinal excitability, and femoral nerve stimulation for voluntary activation (VA) and potentiated twitch (Qtw,pot).
• Neuromuscular assessments were conducted pre- and post-exercise.

Main Results:

• A significant increase in CMJ performance (+4%) was observed post-exercise, confirming PE.
• No significant changes were found in maximum voluntary force, VA, corticospinal excitability, short-interval intracortical inhibition (SICI), or intracortical facilitation (ICF).
• Potentiated twitch (Qtw,pot) significantly declined post-exercise (P < 0.001).

Conclusions:

• Enhanced explosive performance after heavy-resistance exercise was not associated with post-activation potentiation (PAP).
• The study found no evidence of altered neuromuscular function contributing to PE in this context.
• These findings challenge the prevailing hypothesis that PAP is the primary driver of performance enhancement after resistance training.