Figure 3. NOR memory enhancement in exercised male mice.

(A–B) NOR memory enhancement in exercised (RUN) vs. sedentary (SED) animals.

Results represent as Discrimination index (DI). A DI score of >0.20 was set ad hoc to determine proper novel-object discrimination; statistically significant within-group differences were also considered between the training phase and the test phases. (A) Before exercising, mice were unable to discriminate the novel object in a difficult protocol. B) After 6 wk of physical exercise, exercised animals showed memory enhancement. A Mann–Whitney U test indicated that exercised male mice showed significantly higher DI scores than sedentary males in the short-term memory (STM) phase (U = 0, P = 0.021, r² = 0.67) and in the long-term memory (LTM) phase (U = 0, P = 0.02, r² = 0.67). A Friedman test revealed significant differences in the performance of exercised mice throughout the test (X² = 6.5, P = 0.039); post hoc analysis with Wilcoxon signed-rank tests showed significantly higher DI scores in both test phases (Z = −2.023, P = 0.043, r² = 0.41). For comparisons between independent groups, *P < 0.05; for intragroup differences (LTM vs training), +P < 0.05; tendencies 0.05 > #P < 0.09. Extreme values were removed from the analysis. SED, n = 4 biologically independent animals; RUN, n = 5 biologically independent animals. Figure adapted with permission from McGreevy et al, 2019, PNAS ³⁸. The animal procedures were performed following approval by the Committee of Ethics and Animal Experimentation of the Cajal Institute, Ethics Committee of the CSIC, and the Animal Protection Area of the Ministry of Environment of the Community of Madrid. LTM, Long term memory, STM short term memory