This study aimed to examine the effects of aerobic and strength training methodologies, either combined with or without cognitive training, on mitigating cognitive decline. A total of 154 subjects were recruited (72.8 ± 6.1 years, 69% females) and were divided into four groups: i) strength plus cognitive training (STCT, n = 56); ii) strength training (ST, n = 23); iii) aerobic training (AT, n = 41); and iv) aerobic plus cognitive training (ATCT, n = 34). Subjects were previously cognitively assessed and showed cognitive decline (less than 26 points on the Montreal Cognitive Assessment, MoCA). For 12 weeks, all groups performed 3 times a week, for 60 minutes, a training program corresponding to their attributed group. The MoCA test and the Senior Fitness test were applied at the beginning and the end of the intervention. A repeated-measures ANCOVA revealed significant time-by-group interactions for physical performance measures, including the 2-minute step-in-place (p = 0.026), arm curl (p < 0.001), chair sit-and-reach (p < 0.001), back-scratch (p < 0.001), 8-foot up-and-go (p < 0.001), and 6-minute walk tests (p < 0.001). However, no significant improvements were observed for cognitive function (MoCA, p = 0.242) or lower body strength (chair stand, p = 0.411). The AT group showed greater improvements in upper body strength compared to STCT and ST (p < 0.001; d = 0.698; p = 0.004; d = 0.598), while STCT significantly improved flexibility compared to ATCT (p < 0.001; d = 1.049). ATCT had the greatest improvements in aerobic endurance compared to STCT and ST (p = 0.004; d = 0.133; p < 0.001; d = 0.350). It was demonstrated that aerobic and strength training significantly improved overall physical performance in elderly individuals. However, no significant effects were observed on cognitive performance. Although these findings suggest that both aerobic and strength exercise, with or without cognitive training, improve overall physical fitness, further research is needed to determine its impact on cognitive performance.

• Both aerobic training (AT) and strength training (ST), with or without cognitive training, significantly enhanced physical fitness in elderly individuals, with notable improvements in flexibility, aerobic endurance, and upper body strength. The ATCT group demonstrated the greatest gains in aerobic endurance, while STCT achieved better flexibility outcomes.

• None of the training modalities -whether combined with cognitive training or not- produced significant improvements in cognitive performance (assessed by the Montreal Cognitive Assessment) in elderly individuals with pre-existing cognitive decline.

• This study highlights the need for further research to explore strategies that effectively address cognitive improvements in populations with cognitive decline.