Introduction: The early years of life are considered one of the most important and sensitive periods of brain development. Life experiences in early ages, such as physical activity during childhood and adolescence, can lead to long-term brain effects. Physical activity contributes to improved learning by increasing the formation of new neurons in the hippocampus. Studies have shown that high levels of physical activity in children can enhance cognitive performance and reduce anxiety. Additionally, it appears that a rich environment can improve spatial learning and memory by altering the expression of genes related to neuron structure. However, the positive aspects of exercise and physical activity strongly depend on the intensity, volume, and duration of the exercise.

Methodology: In a longitudinal study to examine the long-term effects of exercise, we utilized 40 male rats separated from milk and randomly assigned them to four groups: control, play in an enriched environment, voluntary training, and forced training. From day 28 to 49 (prepuberty), they started exercising under specific conditions. The volume and intensity of exercise were matched as much as possible for the forced and voluntary training groups. Additionally, the time spent and duration of play in the enriched environment were similar to the other two groups. From day 49 to 85, the rats were kept in standard cages without intervention to pass through puberty, and then they underwent Morris water maze and open field tests to examine spatial memory, motor performance, and anxiety-like behavior, respectively.

Results: In the spatial memory variable, significant differences were found in the placement time in the target quadrant between the exercise and control groups (P=0.001, F(3,20)=7). In motor performance, a significant difference in the distance traveled was found among the three trainings groups and the control group (F(3,21)=7, P=0.001). In the examination of anxiety-like behavior in terms of the number and time of entry into the center during adulthood, a significant difference was found between the forced exercise and control groups (F(3,24)=4, P=0.01), indicating that forced training reduced anxiety-like behavior.

Discussion and Conclusion: The results showed that exercise during childhood can lead to positive and enduring effects in later stages of life even after a period of inactivity. Aerobic exercise increased levels of brain-derived neurotrophic factor (BDNF) in the hippocampus, improving spatial memory, and these positive effects persisted into adulthood. It was also demonstrated that exercise during childhood can enhance motor performance in adulthood, with the highest level of spontaneous movement observed in the enriched environment group. Reduction in anxiety-like behavior was observed in the forced training group during adulthood, likely due to the positive stressors of the exercise period and increased resilience.