Objective To investigate the effects of transcranial direct current stimulation (tDCS) combined with resistance training on performance of the college students completing pull-ups, and explore the potential mechanisms underlying the effects of training intervention from the perspective of neuromuscular activity control. Methods A total of 25 male college student volunteers were randomly divided into the tDCS combined with resistance training group (experiment group) and resistance training group (control group). Twelve subjects in the control group received a lat pull-down strength training intervention lasting for 8 weeks, with 4 sets of 12 movement repetitions each, 3 times per week. Thirteen subjects in the experimental group received a 20-minute tDCS before the lat pull-up resistance training intervention. Lat pull-down isometric maximal voluntary contraction (MVC) force, lat pull-down maximal repetitions under 80% one-repetition maximum (1RM) loading, and conventional pull-up exercise were tested before and after the training intervention. Surface electromyography (sEMG) signals of the main exertion muscles of the upper limb were recorded during the pull-up exercise test. Results After the training intervention, the number of pull-ups completed by the experimental group and control group increased by 1.74 times and 1.42 times, respectively. Subjects in both groups showed significant improvements in their MVC and lat pull-down maximal repetitions under 80% 1RM loading. However, there were no statistical differences in these indicators betwenn groups. Activation levels of the agonist muscles brachioradialis, posterior deltoid, and pectoralis major were significantly decreased after the training compared to those before training for both groups. In addition, the coactivation level of the antagonist triceps brachii muscle in the experimental group significantly decreased from 0.50 ± 0.22 to 0.37 ± 0.09 after the training, while there was no significant change in the control group before and after the intervention. Conclusions Eight-week tDCS combined with resistance training and resistance training alone can significantly improve the pull-up performance of college students, which may be related to the fact that both types of training can significantly improve the active muscle contraction capacity. Combined with resistance training, tDCS is more effective in decreasing the coactivation level of triceps brachii during pull-ups and increasing the contraction efficiency of elbow joint muscles.