The Interference Effect in Concurrent Training: Molecular Mechanisms and Practical Implications

Background: Peak neuromuscular power and endurance are distinct qualities of dynamic exercise performance. The concept of the "interference effect" suggests that endurance training may blunt the gains in peak neuromuscular power from resistance training through antagonistic molecular signaling pathways. However, the extent and significance of this interference in human skeletal muscle remain debated. Methods: This review critically explores evidence for the interference effect, examining molecular events mediating peak neuromuscular power and endurance training adaptations. The AMPK-mTORC۱ axis is analyzed as the proposed mechanistic basis, with evidence from electrical stimulation studies, acute exercise transcriptomics, and long-term training interventions. The musculo-cardio-pulmonary exercise test (mCPET) is discussed as a tool demonstrating the complementary relationship between power and endurance. Results: Although endurance and resistance exercise elicit distinct long-term adaptations, they acutely induce remarkably similar signals including hormones, mechanical stress, calcium alterations, and heat stress. Approximately ۶۰% of upregulated genes ۳ hours after endurance exercise are also elevated in response to resistance exercise. The interference effect may become more pronounced as training progresses, but evidence from human concurrent training literature suggests no consistent interference on muscle mass and strength adaptations. The contribution of tissue-resident mononucleated cells to training adaptation remains unknown. Conclusion: The view that peak neuromuscular power and endurance are polar opposites is oversimplified. They are better characterized as "willing partners" in promoting physiological resilience across the spectrum of biological function from youth to aging and health to chronic disease.

کلیدواژه ها:

Concurrent training ، Interference effect ، AMPK ، mTORC۱ ، Neuromuscular power ، Endurance ، Physiological resilience