Purpose To determine the intraocular pressure (IOP) changes caused by the execution of lower body and upper body resistance training exercises leading to muscular failure depending on the exercise phase (concentric vs. eccentric). We also assessed the influence of the exercise type (back squat vs. biceps curl) and level of effort on the IOP response. Methods Nineteen physically active young adults performed four sets (2 exercise type x 2 exercise phase) of 10 repetitions leading to muscular failure while adopting a normal breathing pattern. IOP was measured by rebound tonometry at baseline, after each of the ten repetitions, and after 1 min of recovery. Results There was a main effect of the exercise phase (p < 0.001, eta(2) = 0.56), observing greater IOP values in the eccentric condition of the back squat and concentric condition of the biceps curl. Also, greater IOP values were obtained for the back squat in comparison with the biceps curl (p < 0.001, eta(2) = 0.61), and IOP progressively increases with the level of accumulated effort (p < 0.001, eta(2) = 0.88; Pearson r = 0.97-0.98). Conclusions IOP fluctuates during the different phases of the repetition in dynamic resistance training exercises, being greater IOP values observed during the more physically demanding phases of the exercise (eccentric phase of the back squat and concentric phase of the biceps curl). A heightened IOP response is positively associated with muscle size (back squat > biceps curl) and with the level of effort (number of accumulated repetitions). Based on these findings, highly demanding dynamic resistance training should be avoided when maintaining stable IOP levels is desirable.