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Alzheimer’s Disease (AD) is a complex metabolic and cognitive disorder in which the most common risk factor is age. Exercise capacity is also age-dependent and has become a strong predictor of all-cause morbidity and mortality. Indeed, rat models selectively bred for low and high intrinsic exercise capacity divide in median lifespan by 6-8 months and for several disease risks including insulin resistance, and obesity. The relationship between low exercise capacity and increased complex disease risk and includes neurocognitive impairments. The purpose of this study is to test for differences in cognitive behavior in aged Low-Capacity Runners (LCR) and High-Capacity Runner (HCR) rats. Because epidemiological studies show AD has higher prevalence in females, we evaluated female HCR and LCR rats at 8 months, 10 months, and 24 months of age for exercise capacity using a treadmill running test and assessed cognitive ability by use of a Y-maze to assess spatial memory. Using a computerized video tracking system for analysis, the interaction with previously unexplored spaces was measured by total time spent in the novel arm, number of arm entries and number of alternations to calculate the percent alternation, and number of rearing events to indicate relative exploration. Our results show HCR rats measured significantly longer treadmill distances than LCR rats at all ages. In terms of cognition, there was no significant differences between LCR and HCR rats at 8-months or 20-months of age, however at 24-months HCR rats spent more time than LCR rats in the novel arm but did not differ in number of entries. This implies that HCRs are more spatially aware of a new unexplored territory at later ages compared to LCR rats. Rearing analysis showed a similar pattern where at 24 months of age HCR displayed more rearing events compared to LCR rats, suggesting a significant difference in overall exploratory activity. Testing of blood for increased AD biomarkers amyloid beta42; pTau (Ser610) showed significant differences between LCR and HCR. In summary, female LCR and HCR rats divide for exercise capacity and cognitive function with aging and may be useful as a natural-occurring animal model for the study of energy metabolism and risk for AD and related dementias.