Molecular Adaptations to Concurrent Strength and Endurance Training

Often, athletes and exercise practitioners who want to maximize sports performance and body composition incorporate both strength and endurance regimens into one periodization cycle. This practice is referred to as concurrent training (CT). While some studies suggest that both training-induced adaptations can be developed simultaneously during CT. It has been suggested that when performed in conjunction at high frequency, volume, and intensity, CT may reduce strength training adaptations, which has been defined as the interference effect. Still, the interface of this multifaceted effect is not completely understood. However, advancements in technology have allowed us to increase our understanding of the molecular mechanisms behind the exercise-induced adaptations to both strength and endurance stimuli. Accordingly, a molecular hypothesis has emerged to explain the interference effect from a mechanistic standpoint. Further, when analyzing the current literature in molecular responses to CT, the reader needs to consider multiple factors, as there is an important disparity in the experimental study designs, which may confound interpretations. Therefore, this chapter will critically review the current literature on CT. After reading this chapter, the readers will be able to summarize the current knowledge in acute and chronic molecular responses induced by CT.