A study has found that regular resistance exercise can prevent or delay the onset of Alzheimer's disease symptoms. In an experiment using transgenic mice, resistance training was found to reduce the formation of beta-amyloid plaques and normalize levels of corticosterone, the stress hormone linked to Alzheimer's. Researchers believe that the anti-inflammatory effects of resistance training could be the main reason for its effectiveness in preventing Alzheimer's. The study concluded that resistance exercise could be an affordable and accessible therapy for Alzheimer's patients.
Experiments with mice showed that four weeks of weight training was sufficient to reverse the physical and behavioral changes characteristic of the disease.
Regular physical exercise, such as resistance training, can prevent alzheimer disease, or at least delay the onset of symptoms, and serves as a simple and affordable therapy for Alzheimer's patients. This is the conclusion of an article published in the magazine Frontiers in Neuroscience by Brazilian researchers affiliated with the Federal University of São Paulo (UNIFESP) and the University of São Paulo (USP).
Although older people and people with dementia are unlikely to be able to do long daily runs or other high-intensity aerobic exercise, these activities are the focus of most scientific studies on Alzheimer's disease. The World Health Organization (WHO) recommends resistance exercise as the best option to train balance, improve posture and prevent falls. Resistance exercise involves the contraction of specific muscles against external resistance and is considered an essential strategy for increasing muscle mass, strength, and bone density, and for improving overall body composition, functional capacity, and balance. It also helps prevent or mitigate sarcopenia (muscular atrophy), making it easier to perform daily tasks.
To observe the neuroprotective effects of this practice, researchers from the Physiology and Psychobiology Departments of UNIFESP and the Biochemistry Department of the USP Institute of Chemistry (IQ-USP) conducted experiments with transgenic mice with a mutation responsible for the accumulation of beta-amyloid plaques in the brain. The protein accumulates in the central nervous system, disrupts synaptic connections, and damages neurons, all of which are hallmarks of Alzheimer's disease.
During the study, financed by FAPESP, the mice were trained to climb a 110 cm ladder with an 80° inclination and 2 cm between rungs. Loads corresponding to 75%, 90% and 100% of their body weight were attached to their tails. The experiment mimicked certain types of resistance training performed by humans in gyms.
At the end of a four-week training period, blood samples were taken to measure plasma levels of corticosterone, the hormone in mice equivalent to cortisol in humans; increasing levels in response to stress increases the risk of developing Alzheimer's disease. Hormone levels were normal (the same as those found in the control group comprising animals without the mutation) in the exercise-trained mice, and analysis of their brain tissue showed decreased beta-amyloid plaque formation. .
“This confirms that physical activity can reverse the neuropathological alterations that cause the clinical symptoms of the disease,” said Henrique Correia Campos, first author of the article.
“We also observed the behavior of the animals to assess their anxiety in the open field test ( which measures avoidance of the central area of a box, the most stressful area ) and found that resistance exercise reduced hyperlocomotion to levels similar to controls among mice with the Alzheimer's-associated phenotype,” said Deidiane Elisa Ribeiro, co-author of the article and researcher at the IQ-USP Neurosciences Laboratory. Agitation, restlessness, and wandering are common early symptoms of Alzheimer's disease and other types of dementia.
“Resistance exercise is increasingly proving to be an effective strategy to prevent the onset of sporadic Alzheimer's symptoms ( not directly caused by a single inherited gene mutation ), which is multifactorial and may be associated with aging, or to delay its onset in familial Alzheimer's. The main possible reason for this effectiveness is the anti-inflammatory action of resistance exercise”, said Beatriz Monteiro Longo, last author of the article and professor of neurophysiology at UNIFESP.
Literature review
The animal model study was based on a literature review published in Frontiers in Neuroscience where the same UNIFESP group compiled clinical evidence that the benefits of resistance exercise include positive effects on cognitive dysfunction, memory deficits, and behavioral problems in Alzheimer's patients, concluding that it may be an affordable alternative or adjuvant therapy. .
Researchers from the Federal University of Rio Grande do Norte (UFRN) and the Federal University of Ouro Preto (UFOP) in Brazil also participated in the study.
“Alzheimer's does not only affect the patient. The whole family is affected, especially in low-income households,” said Caroline Vieira Azevedo, first author of the review article and a graduate student at UNIFESP. “Both articles offer information that can be used to stimulate the creation of public policies. Imagine the cost savings if the onset of symptoms in older patients is delayed by ten years.”
Reference: “Neuroprotective effects of resistance physical exercise in the APP/PS1 mouse model of Alzheimer's disease” by Henrique Correia Campos, Deidiane Elisa Ribeiro, Debora Hashiguchi, Talita Glaser, Milena da Silva Milanis, Christiane Gimenes, Deborah Suchecki, Ricardo Mario Arida, Henning Ulrich and Beatriz Monteiro Longo, April 6, 2023, Frontiers in Neuroscience
DOI: 10.3389/fnins.2023.1132825