Concurrent strength and endurance training: from molecules to man.
Level 5 - mechanism / opinion, no new human data
Narrative review of historical literature and molecular signaling mechanisms.
PubMed 17095931 · doi:10.1249/01.mss.0000233795.39282.33
What was done
This narrative review summarizes literature on concurrent strength and endurance training, focusing on the interference effect where simultaneous endurance work can impair strength development. The authors examine cellular signaling pathways to propose a molecular explanation for the incompatibility between these two training modalities.
What was found
The abstract reports no numerical values, effect sizes, or participant numbers. It describes a mechanistic pathway in which endurance-induced activation of AMPK acts antagonistically toward the muscle protein-synthesis machinery by inhibiting mTOR and its downstream targets, explaining the observed blunting of strength adaptations.
Why it matters
It provides a molecular framework (the AMPK-mTOR hypothesis) to explain the phenotypic interference effect between endurance and resistance exercise first described by Hickson in 1980.
Limits
As a narrative review, it lacks a systematic search protocol, risk of bias assessment, and quantitative synthesis. The proposed intracellular signaling pathway is primarily theoretical and mechanistic, and the abstract does not define the training parameters (volume, frequency, timing) or populations where this interference effect is most pronounced.
Cited by
- supports Robert Hickson's classic research suggested an interference effect between concurrent endurance and resistance training on strength gains.
- supports The chronic interference hypothesis was based on animal and rodent models showing cardiovascular exercise upregulates AMPK, which blunts the anabolic mTOR pathway.