Increases in muscle size and strength are influenced by the mechanical and metabolic stresses imposed
by resistance training. Mechanical stress is induced by the use of high-intensity training and it is believed
it activates a larger percentage of muscle fibers. Conversely, metabolic stress is generated by high training
volumes with moderate intensities using short rest intervals. This training paradigm results in greater fatigue
and potentially stimulates a greater anabolic hormone response to exercise. Although evidence exists for
both strategies, it still remains inconclusive whether one training paradigm is more advantageous than the
other regarding muscle hypertrophy development. In untrained adults, the novelty of most resistance training
programs may be sufficient to promote hypertrophy and strength gains, whereas greater training intensity
may be more beneficial for trained adults. However, the body of well-designed research in this advanced
population is limited. Therefore, the purpose of this brief review is to discuss the merits and limitations of
the current evidence.