Original Research Effect of Different Types of Loads on the Force- Velocity Relationship Obtained During the Bench Press Throw Exercise Marko Cosic, 1 Olivera M. Knezevic, 2 Aleksandar Nedeljkovic, 1 Sasa Djuric, 3 Milena Z. Zivkovic, 1 and Amador Garcia-Ramos 4,5 1 Faculty of Sport and Physical Education, The Research Center, University of Belgrade, Belgrade, Serbia; 2 IInstitute for Medical Research, University of Belgrade, Belgrade, Serbia; 3 Faculty of Sport, Institute of Kinesiology, University of Ljubljana, Ljubljana, Slovenia; 4 Department of Physical Education and Sport, Faculty of Sport Sciences, University of Granada, Granada, Spain; and 5 Department of Sports Sciences and Physical Conditioning, Faculty of Education, CIEDE, Catholic University of the Most Holy Concepci ´ on, Concepci ´ on, Chile Abstract Cosic, M, Knezevic, OM, Nedeljkovic, A, Djuric, S, Zivkovic, MZ, and Garcia-Ramos, A. Effect of different types of loads on the force-velocity relationship obtained during the bench press throw exercise. J Strength Cond Res XX(X): 000–000, 2019—This study aimed (a) to evaluate the degree of linearity of the force-velocity (F-V) relationship across different types of loads, (b) to compare the magnitude of the F-V relationship parameters (maximum values of force [F 0 ], velocity [V 0 ], and power [Pmax]) between the different types of loads, and (c) to explore the concurrent validity of F 0 with traditional measures of maximal strength. The F-V relationships of 15 physically active men (age: 20.9 6 2.0 years, bench press 1 repetition maximum relative to body mass: 1.20 6 0.10 kg·kg 21 ) were determined during the bench press throw exercise using predominantly gravitational (W), inertial (I), and combined (W + I) loads. The bench press maximal isometric force (F iso ) and the 1RM were also assessed. The individual F-V relationships were highly linear regardless of the type of load considered (median r [range] 5 0.98 [0.94, 1.00]). The W + I load provided the largest value of F 0 (972 6 45 N; 6.0 and 14.6% higher than W and I, respectively), the I load the largest value of V 0 (2.99 6 0.34 m·s 21 ; 40.4 and 20.1% higher than W and W + I, respectively), and the W load the lowest value of Pmax (501 6 46 W; 222.7 and 217.1% lower than I and W + I, respectively). The F 0 obtained from the W load presented the highest association with F iso and 1RM values (r . 0.90). The W + I load and the I load should be recommended to work closer to the F 0 and V 0 capacities, respectively. However, the W load should be recommended to assess maximal strength capacity through the value of F 0 . Key Words: inertia, maximum force, maximum velocity, maximum power, weight Introduction The relationship between the velocity (V) of muscle contraction and the force (F) that it can produce is one of the main muscular properties (10). Therefore, it is not surprising that the F-V re- lationship has been frequently used to assess muscular function (14). Early studies explored the F-V relationship of isolated muscles and described the hyperbolic shape of the F-V relation- ship (10,29). However, a growing number of research have been conducted in recent years to explore the F-V relationship during more functional tasks that involve multiple joints and muscles (e.g., vertical jumps, running, cycling, throws, etc.) (7,26,27,30). Contrary to the hyperbolic F-V relationship of isolated muscles, the F-V relationship of the muscles involved in multijoint func- tional tasks can be modeled with a linear regression (1,13). The modeling of the linear F-V relationship allows to determine the maximal capacities of the muscles involved in the movement to produce F (F 0 ), V (V 0 ), and power (Pmax). The typical procedure used to determine the F-V relationship during multijoint exercises consists of recording F and V outputs against different external loads (7,25,30). The recorded F during this standard procedure has 2 main components: weight (mass 3 gravity) and inertia (mass 3 acceleration). However, the most standard type of load (weight 1 inertia; W 1 I) can be modified to provide almost exclusively gravitational (W) or inertial (I) loads (6,16). A predominantly W load can be applied with isokinetic devices or through long and extended rubber bands pulling in the opposite direction of the movement, while a predominantly I load has been applied with flywheel devices or through long and ex- tended rubber bands pulling in the same direction of the move- ment (6,15,17,24). The type of load (W, I, or W 1 I) has proven to influence both vertical jump and bench press throw (BPT) performance (16,17). Namely, power output was higher when applying a W load, followed by a W 1 I load, and finally an I load; F output was lower for I loads compared with the W and W 1 I loads; and V was lower for W 1 I loads compared with W and I loads (16,17). However, the effect of the type of load on the F-V relationship remains virtually unexplored. It would be of interest to determine both the degree of linearity of the F-V relationship obtained exclusively from the W and I loads and the differences in the magnitude of the F-V relationship parameters with respect to the standard F-V relationship (W 1 I). This information is im- portant since it has been shown that an 8-week bench press training performed with different types of loads is able to selec- tively influence the changes in the magnitude of the F-V Address correspondence to Dr. Amador Garcia-Ramos, amagr@ugr.es. Journal of Strength and Conditioning Research 00(00)/1–7 ª 2019 National Strength and Conditioning Association 1 Copyright © 2019 National Strength and Conditioning Association. Unauthorized reproduction of this article is prohibited.