A systematic review published in the Journal of Aging and Physical Activity concluded that older individuals who engage in more physical activities exhibit greater brain volume, notably in regions associated with cognition, memory, and reasoning. The analysis gathered data from nearly 2,700 people aged 60 or older, demonstrating a consistent correlation between high levels of daily movement and a structurally better-preserved brain, underscoring the relevance of exercise in preventing cognitive decline.
The research was conducted by student Sara Oliveira Dias de Lucena, a FAPESP scholarship holder, under the guidance of Lucas Melo Neves, a professor in the Physical Education Department of the Institute of Biosciences of the State University of São Paulo (IB-Unesp), on the Rio Claro campus. The researchers examined 19 observational studies, covering data from 2,684 participants with an average age of 70, evaluating 76 distinct brain structures and regions.
The involved studies measured brain volume through magnetic resonance imaging and participants' physical activity levels using questionnaires or accelerometers. The results indicated that the most active elderly had a higher total brain volume, in addition to showing greater volume in regions crucial for cognition, such as the hippocampus.
Lucas Melo Neves commented that while the population associates exercise with muscle hypertrophy, this study suggests a parallel in the brain: greater physical activity leads to a more preserved brain. He expressed hope that this connection between movement and brain health will become as evident as the relationship between training and muscle mass gain in the coming years.
According to Neves, it is natural for the brain to undergo gradual structural changes with aging. From middle age, a progressive reduction in brain volume is observed, caused by neuronal loss, decrease in neural connections, and alterations in white matter, which is responsible for brain communication.
He emphasized that this process is part of healthy aging but can affect functions such as attention, memory, and reasoning speed. Regions like the hippocampus, vital for forming new memories, are particularly vulnerable over the years. However, the intensity of this loss varies individually and can be modulated by factors such as lifestyle, level of physical activity, management of chronic diseases, and continuous cognitive stimulation.
The hippocampus is a widely studied area and is among the first structures to show atrophy with aging or in conditions such as Alzheimer's. The review of studies confirmed the link between physical activity and a larger hippocampus volume. Neves classified this data as clinically relevant, given that the hippocampus is very sensitive to aging.
In some studies included in the review, elderly individuals who met the minimum physical activity recommendation of the World Health Organization (WHO)—approximately 150 minutes per week—showed a hippocampus 7% to 10% larger compared to their less active peers. The professor clarified that although the percentages may seem modest, the difference is clinically significant because a more preserved hippocampus is linked to better memory performance and greater cognitive reserve.
White matter, another structure with a positive association in the review, remained preserved in more active people. It functions as a network of brain connections, facilitating efficient communication between different parts of the brain. Changes in this area are associated with slow thinking and executive difficulties; keeping this network intact can promote faster information processing during aging.
The mechanisms behind this relationship have been the subject of scientific study for some time. One hypothesis is that regular exercise stimulates the production of neurotrophic factors, such as BDNF, which promote neuronal survival and plasticity. Furthermore, regular practice improves cerebral blood flow, encourages the creation of new vessels, and may reduce chronic inflammatory processes. Neves stated that physical activity establishes a biological environment more conducive to brain health, aiming not only at preservation but also at stimulating structural adaptations.
Despite the consistency of the findings, Neves emphasized that the analyzed studies are observational in nature, which prevents stating causality. It is possible that individuals with structurally more preserved brains have a greater predisposition to be active. To overcome this methodological limitation, the authors are developing a new review focused on intervention studies, which monitor elderly people in structured exercise programs to verify a direct effect on brain volume preservation or increase.
In conclusion, Neves reiterated that the main message is clear: regular movement is associated with a healthier brain in old age. In a scenario of population aging and increasing dementias, preventive strategies are becoming increasingly urgent.
