Purpose. The purpose of the study was to estimate the influence of the symmetrical movements, mirror (breaststroke) and translational (front crawl) ones, on the dynamical asymmetry of upper limbs. Basic procedures. Thirty six students (15 males and 21 females) took part in the study. The forces produced by the subjects' upper limbs during breaststroke and front crawl simulation on the swimming ergometer (Weba, Germany) were recorded. Then the coefficient of dynamical asymmetry was computed. Main findings. Breaststroke movements revealed lower dynamical asymmetry of upper limbs than front crawl ones for men as well as for women. Greater differences between the types of movement under study were observed in women. Conclusions. It might appear that males can use interchangeably both techniques during symmetrization. However, for women, first of all the mirror symmetry movements should be used. So, selection of exercises for symmetrization of movements of upper limbs should be based on the gender factor, too.