%0 Journal Article
%T Adaptations in athletic performance and muscle architecture are not meaningfully conditioned by training free-weight versus machine-based exercises: Challenging a traditional assumption using the velocity-based method.
%A Hernández-Belmonte A
%A Buendía-Romero Á
%A Franco-López F
%A Martínez-Cava A
%A Pallarés JG
%J Scand J Med Sci Sports
%V 33
%N 10
%D 2023 Oct 21
%M 37340878
%F 4.645
%R 10.1111/sms.14433
%X <B>BACKGROUND: </B>Although the superior effectiveness of free-weight over machine-based training has been a traditionally widespread assumption, longitudinal studies comparing these training modalities were scarce and heterogeneous.<BR><B>OBJECTIVE: </B>This research used the velocity-based method to compare the effects of free-weight and machine-based resistance training on athletic performance and muscle architecture.<BR><B>METHODS: </B>Thirty-four resistance-trained men participated in an 8-week resistance training program allocated into free-weight (n = 17) or machine-based (n = 17) groups. Training variables (intensity, intraset fatigue, and recovery) were identical for both groups, so they only differed in the use of a barbell or specific machines to execute the full squat, bench press, prone bench pull, and shoulder press exercises. The velocity-based method was implemented to accurately adjust the planned intensity. Analysis of covariance and effect size (ES) statistics were used to compare both training modalities on a comprehensive set of athletic and muscle architecture parameters.<BR><B>RESULTS: </B>No between-group differences were found for any athletic (p ≥ 0.146) and muscle architecture (p ≥ 0.184) variable. Both training modalities significantly and similarly improved vertical jump (Free-weight: ES ≥ 0.45, p ≤ 0.001; Machine-based: ES ≥ 0.41, p ≤ 0.001) and lower limb anaerobic capacity (Free-weight: ES ≥ 0.39, p ≤ 0.007; Machine-based: ES ≥ 0.31, p ≤ 0.003). Additionally, the machine-based group meaningfully enhanced upper limb anaerobic power (ES = 0.41, p = 0.021), whereas the free-weight group significantly improved the change of direction (ES = -0.54, p = 0.003) and 2/6 balance conditions analyzed (p ≤ 0.012). Changes in sprint capacity (ES ≥ -0.13, p ≥ 0.274), fascicle length, and pennation angle (ES ≤ 0.19, p ≥ 0.129) were not significant for either training modality.<BR><B>CONCLUSIONS: </B>Adaptations in athletic performance and muscle architecture would not be meaningfully influenced by the resistance modality trained.