Adaptation to Concurrent Training: Role of Endurance Training Intensity

The simultaneous integration of both endurance and resistance exercise (RE) into a periodised training regime is termed concurrent training. As both exercise modes promote adaptations at both whole-body and skeletal muscle levels that improve oxidative as well as functional capacity, concurrent training is an attractive exercise strategy for improving markers of cardiometabolic health and athletic performance. Since the classic work of Hickson (1980), numerous investigations have shown that concurrent training, relative to resistance training (RT) performed alone, can attenuate improvements in maximal strength, hypertrophy, and indices of power development, with no negative impact on V̇O2max. This has been variously described as the interference effect or concurrent training effect. Despite the majority of the literature supporting the existence of the interference effect, some studies have not observed any evidence of an interference effect, or rather that some adaptations may be more susceptible to interference than others. The equivocal nature of this phenomenon suggests variations in the prescription of individual training variables may modulate the degree of interference seen with concurrent training. Identification of training variables mediating the interference effect will therefore allow for targeted exercise prescription to minimise interference during concurrent training