Vol. 16, Issue 1, december 2020.




Borko Petrović1, Aleksandar Kukrić1, Radenko Dobraš1, & Nemanja Zlojutro1
1University of Banja Luka, Faculty of physical education and sport,Bosnia and Herzegovina.

 UDC: 796.012.112



This study aims to determine whether maximum isometric muscle strength, exerted at a certain angle in the knee joint (80 °, 110 °, and 140 °), may be used as a predictor of 1RM in the squat movement task. A group of twenty-four male students (N = 24) took part in the research in 2 separate sessions and 7 days of rest between each. In the first session, the anthropometric measurements and assessment of muscle strength, that is 1RM, were measured by maximum repetition to failure method on the Smith machine. The maximum isometric force (Fmax) of the leg muscles was measured by the Alternating Consecutive Maximum Contraction Test in laboratory conditions on a Smith machine using a dynamometer probe and the Globus Ergo Tesys System 1000 software system. Analyzing the results based on linear regression, the authors conclude that, with an accuracy of 84.5%, we can estimate 1RM in the squat exercise measuring the maximum isometric force exerted at an angle in the knee joint of 140 °. The results obtained by this research can be used in practice when assessing 1 RM based on the measurement of the maximum isometric force for a given movement task.

Key words: muscle strength, prediction, 1RM, squat

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Petrović, B., Kukrić, A., Dobraš, R., & Zlojutro, N. (2019). Isometric muscle  force  as a predictor of a maximal muscle effort in the leg press test. Sportlogia 15 (1), 81-89.

To cite this article:
Petrović, B., Kukrić, A., Dobraš, R., & Zlojutro, N. (2020). Maximum isometric muscle strength as a predicror of one repetition maximum in the squat test. Sportlogia 16 (1), 161-172.



Received: 09.11.2020.
Accepted: 30.11.2020.

Borko Petrović, Ph. D.
Faculty of Physical Education and Sport, University of Banja Luka
Bulevar vojvode Petra Bojovića 1 A, 78 000 Banja Luka, Bosnia and Herzegovina