ISOMETRIC MUSCLE FORCE AS A PREDICTOR OF A MAXIMAL MUSCLE EFFORT IN THE LEG PRESS TEST

This research aimed to determine whether the manifestation of maximum isometric muscle force at a certain joint angle (80°, 110°, and 140°) can act as a predictor of 1-RM in a leg press movement task. The research was carried out in a group of twenty-four (N=24) male students, within two separated sessions, with seven days of rest between each. The anthropometric measurements and muscle force assessment that is 1-RM, was executed through the training-to-failure method on a leg press machine (leg press, V-Gym Croatia) in the first session. Maximum isometric force (Fmax) of leg muscles was measured using maximum consecutive contractions test, in the laboratory conditions, on leg press machine with the help of dynamometer probe and Globus Ergo Tesys System 1000 software. Having analyzed the results obtained on the linear regression basis, the authors have, with 84,5% precision, inferred that it is possible to assess 1-RM in leg press exercise based on maximum isometric force exerted at the angle of the knee joint of 140°. The results attained may be applied in practice when assessing 1-RM, based on maximum isometric force measurement for a given movement task.