Aerobic exercise in people with Alzheimer's disease – Protocol parameters in randomized controlled trials: scoping review
Creators: name: Souza, Renan
name: Clodoaldo Antonio De Sá
name: CRISTIANO PADILHA
name: Sinval Adalberto Rodrigues Junior
Publisher: name: OSF Registries
Year: 2024
Subjects: subject: Medicine and Health Sciences
subject: Aerobic physical exercise
subject: Alzheimer's disease
subject: Protocol
subject: Scoping Review

description: Human aging is a natural, progressive and dynamic process, associated with functional, physiological, morphological, biochemical, psychological and, consequently, social changes. The effects caused by these changes make the elderly more susceptible to pathologies, including neurodegenerative ones (SIQUEIRA et al., 2019). 
According to the World Health Organization (WHO), dementia affected approximately 5% of the older population in 2015, that is, people over 60 years of age. It should be noted that although age is the strongest known risk factor for cognitive decline, dementia is not an inevitable exclusivity of aging (WORLD HEALTH ORGANIZATION, 2019).
Cognitive decline may result from physiological changes expected during the aging process. However, changes of varying degrees that affect cognition above what is expected for age and education may be the transition stage to dementia (CHARCHAT-FICHMAN et al., 2005; MENDES et al., 2018). Among the conditions of dementia and neurological diseases that lead to cognitive impairment, Alzheimer's Disease (AD) and Parkinson's Disease (PD) stand out, in particular, due to their relatively high prevalence (CARDOSO; LANDENBERGER; ARGIMON, 2017). The prevalence of both increases with age. It is estimated that AD affects 55 million people worldwide (NICHOLS; VOS, 2021), and PD affects 10 million of the population over 60 years old (TYSNES; STORSTEIN, 2017), figuring as the first and second most common neurodegenerative diseases worldwide. 
Epidemiological studies demonstrate that elderly people with a decline in cognitive capacity are at greater risk of developing dementia, with a higher prevalence of AD and PD (AARSLAND et al., 2017; CASS, 2017). Dementia is a chronic and progressive syndrome, characterized by compromising cognitive functions, such as memory, thinking and behavior, affecting the performance of daily life activities (MENDES et al., 2018).
The last few decades have seen major efforts to update and improve the evidence on how to prevent Alzheimer's. AD is a progressive neurodegenerative pathology, characterized by memory loss, attention deficit, verbalization difficulties, cognitive damage, impairments in visuospatial skills and decline in functional capabilities (SIQUEIRA et al., 2019). It is the main cause of dementia at the end of adult life and is associated with a significant burden and increased morbidity and mortality in the elderly (CASS, 2017).
AD is a complex multifactorial disorder and multi-domain interventions targeting risk factors and disease mechanisms simultaneously may be necessary for optimal preventive effects (NGANDU et al., 2015). Current approaches focus on helping people maintain mental function, manage behavioral symptoms, and slow certain problems such as memory loss. In addition to drug treatment, scientists are looking for non-drug interventions, such as physical exercise, diet, cognitive training and combinations of these approaches as a way to delay and prevent the disease, as well as treat its symptoms (NIA, 2021).
Studies have addressed the positive effects of exercise on AD. The practice of physical exercise, whether chronic or acute, has beneficial effects on the nervous system of the elderly, with positive evidence for neuroprotective and neurogenic effects on the central nervous system and on the structures and functions of the peripheral nervous system and the autonomic nervous system, such as improvement in the activation of motor units and a protective factor for cardiovascular dysfunctions (SCIANNI et al., 2019).