Objective: To explore the effects of different types of acute exercise on the working memory of sedentary college students，so as to provide a basis for exercise intervention. Methods: From April 15 to May 30, 2023, a total of 42 sedentary college students were recruited from one university in Beijing. Using a single blind, completely randomized experimental design, participants were randomly assigned to an open skill exercise group, a closed skill exercise group, or a control group, with 14 participants in each group. The open skill exercise group engaged in 30 minutes of badminton, the closed skill exercise group performed 30 minutes of running, and the control group remained seated for 30 minutes. All participants completed a 2-back working memory task and had their electroencephalogram (EEG) data recorded before and after the intervention. Results: The accuracy rates of the open skill exercise group, closed skill exercise group, and control group (0.90±0.06, 0.94±0.05; 0.88±0.05, 0.94±0.05; 0.85±0.10, 0.90±0.06) showed a significant main effect of time ( F=37.14, P <0.01). Reaction times [(923.65±145.08, 711.56± 140.93 ; 909.59±180.28, 807.85±169.66; 917.05±166.35, 871.86±186.07)ms] showed both a significant main effect of time and a significant interaction between group and time ( F=70.55, 11.83, P <0.01). Repeated measures ANOVA revealed that all three groups improved in accuracy and reaction time compared to pre test values, with no significant difference in accuracy between groups. However, the reaction time of the open skill exercise group was significantly faster than that of the control group ( P <0.05), while there was no significant difference between the closed skill exercise group and the control group ( P >0.05). For EEG data, the P2 amplitude showed a significant main effect of time and a significant interaction between groups and time ( F=10.60, 7.66, P < 0.01 ), with the open skill exercise group exhibiting a higher P2 amplitude than the control group ( P <0.05), while the closed skill exercise group showed no significant difference compared to the control group ( P >0.05). The N2 amplitude showed a significant main effect of time ( F=5.94, P <0.05). The P3 amplitude showed significant main effects of time and electrode position, as well as a significant interaction between groups and time ( F=23.16, 4.53, 5.85, P <0.05), with both exercise groups exhibiting higher P3 amplitudes than the control group ( P <0.05), but no significant difference between the two exercise groups ( P >0.05). Conclusion Open skill exercise is more effective than closed skill exercise in improving the working memory of sedentary college students.