How does concentric flywheel resistance training (FRT) differ to traditional resistance training (TRT)? We often think that the advantage of FRT is in the eccentric phase, but it may also be in the concentric phase. One of the things you notice is that with FRT the concentric effort and therefore forces are relatively high throughout the motion. With TRT you need to overcome the inertia of the loaded bar for example, and accelerate the bar which establishes momentum (mass x velocity), which in turn you need to decelerate at some time during the lift. For example, Elliot et al (1989) reported that only 48.3% of the concentric phase was spent accelerating a bench press load of 81% 1RM (Med Sci Sports Exerc 1989; 21 (4): 450-62).
With FRT this means that you are overloaded more so throughout the entire concentric phase, which could provide significant advantages to your partial as well as full range of motion force capability. Joshua Naterman summarised it perfectly by stating, “in many ways the physics that power the flywheel allow for more consistent force application in terms of approximate % of 1RM at that point in the ROM throughout the entire exercise, which in my mind is primarily an advantage.”