Abstract des Autors

Fixed weight machines can play an important role in the resistance-training protocol of both the recreational lifter and the competitive athlete. Advantages of machines include (a) increased body stability from the adjustable seat and back support, making machines easy to use; (b) less skill requirements; and (c) no spotting requirement. On the other hand, there are several reasons why a program should be based on total-body free-weight movements (rather than isolated machines). The first reason is power. The greater the effort (and acceleration/velocity achieved) with a given weight, the higher the power development. The second reason is motor skills. Such power transmission from the ground up through the "kinetic chain" also develops muscular synergy, stabilization, and proprioception. This in turn carries over to athletic movements like running, jumping, blocking, and tackling. The third reason is the systemic effect. The greater the exertion in the big lifts, the higher the production of endogenous hormones, thereby stimulating overall muscle mass and strength to a much greater degree. Moderate weights for high reps, and high-intensity endurance activities in general, tend to maximize the somatotropin response. Heavy weights for low reps, and brief maximal (or near-maximal) efforts in general, tend to maximize the testosterone response. Verf.-Referat