Cuevas-Aburto, J.Ulloa-Díaz, D.Barboza-González, P.Chirosa-Ríos, L.J.García-Ramos, A.2019-12-172019-12-172018PeerJ, 2018(11), art. no. e5835.2167-8359DOI: 10.7717/peerj.5835http://repositorio.unab.cl/xmlui/handle/ria/11517Indexación: Scopus.Background: The aim of this study was to examine whether the addition of very light loads for modeling the force-velocity (F-V) relationship during the bench press (BP) exercise can confirm its experimental linearity as well as to increase the reliability and concurrent validity of the F-V relationship parameters (maximum force (F0), maximum velocity (V0), F-V slope, and maximum power (Pmax)). Method: The F-V relationship of 19 healthy men were determined using three different methods: (I) 6-loads free method: six loads performed during the traditional free-weight BP exercise (≈ 1-8-29-39-49-59 kg), (II) 4-loads free method: four loads performed during the traditional free-weight BP exercise (≈ 29-39-49-59 kg), and (III) 4-loads Smith method: four loads performed during the ballistic bench press throw exercise in a Smith machine (≈ 29-39-49-59 kg). Results: The linearity of the F-V relationship was very high and comparable for the three F-V methods (p = 0.204; median Pearson's correlation coefficient (r) = 0.99). The three methods were ranked from the most to the least reliable as follows: 6-loads free (coefficient of variation (CV) range = 3.6-6.7%) > 4-loads Smith (CV range = 4.6-12.4%) > 4-loads free (CV range = 3.8-14.5%). The higher reliability of the 6-loads free method was especially pronounced for F-V slope (CVratio 1.85) and V0 (CVratio 1.49) parameters, while the lowest difference in reliability was observed for F0 (CVratio 1.27). The 6-loads free and 4-loads free methods showed a very high concurrent validity respect to the 4-loads Smith method for F0 and Pmax (r 0.89), a moderate validity for the F-V slope (r = 0.66-0.82), and a low validity for V0 (r 0.37). Discussion: The routine testing of the F-V relationship of upper-body muscles through the BP exercise should include trials with very light loading conditions to enhance the reliability of the F-V relationship. © Copyright 2018 Cuevas-Aburto et al.enMaximum forceMaximum powerMaximum velocityMuscle mechanical capacitiesArtículo