Muscle Hypertrophy Responses to Changes in Training Volume: A Retrospective Analysis.

This study assessed associations between changes in the weekly number of sets performed and the percentage change in muscle thickness of the biceps (MT) and triceps (MT) brachii muscles. Through a retrospective analysis, sixty-eight resistance-trained subjects that participated in previous studies had their previous training volumes analyzed and compared to the volume imposed during each individual study. The relationship between variables was determined through correlation and a k-cluster analysis was performed to subdivide the participants into three groups and classified as:<0%; 0-50%, and >50% increase in the number of sets for both muscle groups.