Exploring the theory of successful aging

One of the main challenges for science and critical approaches to the theory of successful aging is to outline a common concept (^{AshaRani et al., 2022}; ^{Menassa et al., 2023}). What frequently occurs is what ^{Katz & Calasanti (2015)} describe as follows: one of the greatest challenges faced by those working within the framework of successful aging is the inconsistency across studies in terms of conceptualization and measures, so much so that the meaning of successful aging is often more implied than delineated. Consequently, a real tension of health measures, lifestyles, political agendas and anti-aging ideals have been forming in a paradigm of theoretical concept cuts. Historically referred to as “productive aging”, “positive aging”, “ideal aging”, “effective aging”, “independent aging”, and “healthy and active aging”, these terms together promote an industry of scientific production (^{Katz & Calasanti, 2015}).

Studies on aging in the field of psychology are relatively new. During the first six decades of the 20th century, the psychology of aging considered the perspective of old age as a period of decline. However, the concept of development as a lifelong phenomenon had attracted the attention of scholars since the 18th and 19th centuries (^{Neri, 2007}). However, it is known that the scientific and cultural environment of that time did not permit different thoughts about maturity and old age.

According to ^{Menassa et al. (2023)}, successful aging means the acceptance and desire of the elderly person for the process of increasing an active life and, at the same time, maintaining, as far and as long as possible, the activities and attitudes of middle age. It is a theory that orchestrated a way of life that was considered by society appropriate for older people. ^{Menassa et al. (2023)} explain that the field of studies on successful aging started to expand discussions by the 1990s, with new social contours.

^{Menassa et al. (2023)} proposed the theory of successful aging based on an adaptation in response to changes, resources, and restrictions. Even when this behavior will be (un)successful. The authors explain that aging can be characterized as a variable balance between gains and losses (in resources), in which losses will increasingly exceed gains.

There are many criticisms directed at theories of successful aging, particularly at the purely biological model that defines aging as the absence of chronic diseases and the preservation of physical and cognitive functions (^{Lin et al., 2020}; ^{Reich et al., 2020}). To better illustrate the concepts discussed, Table 1 summarizes the main aspects of successful aging.

Until the mid-1970s, the perspective on successful aging was still very limited, mainly because old age was reduced to levels of physical activity and social participation that, supposedly, should be lower due to the advanced age. This distorted view of a purposeless old age has been constructed by society for decades. Ageism, i.e., discrimination against people based on age, often prevents older persons from pursuing their goals. As a consequence, the situation of older adults is marginalized or stigmatized. The study by ^{Podhorecka et al. (2022)} indicates that, by recognizing the meanings and purposes of life of older adults, it is possible to alleviate negative experiences and to promote successful aging. This implies a cultural change, which requires contributions so that the inclusion of older adults is conceived appropriately and they are valued.

One aspect portrayed in the literature is the relationship between successful aging and its consequences related to prejudices about old age that are a barrier to successful aging. According to ^{Podhorecka et al. (2022)}, ageism is a concept that comprises prejudice against old age and that exerts effects on society as a whole. This includes restricting the inclusion of older people in the world and in their different social spaces, as well as stereotypical attitudes and a lack of alternatives for preserving quality of life. The effects also affect the barriers to the active aging process. The social marginalization of older adults increases their health problems, with a negative impact on health systems and the expansion of attitudes towards life purposes (^{Podhorecka et al., 2022}).

Yu (2022) describes the relationship between people who pursue their goals and who face frustrating situations in their daily lives, momentarily exhibiting negative attitudes. Becoming or having a subject over 60 years of age, a productive citizen inclined to the intricacies of the consumer market or simply physically active, is therefore not a simple fact. It is important to consider that purposes can simply be achieved with different meanings. However, this will depend on life experiences and stories (^{Podhorecka et al., 2022}) and, possibly, the influence of physical activity.

According to Zhang and Chen (2021), in the case of older people such as the oldest one, the intensity of physical activity decreases with age. This is also observed for life purposes but they continue to be present. It is therefore necessary to determine whether differences between types of physical activities, sociocultural and demographic aspects, and perception of aging play a role in issues of ageism and life purpose.

The theoretical model of ^{Baltes (1996)} can be used to explain successful development in terms of goal selection, the optimization of means to achieve these goals, and the pursuit of compensation when the means available to achieve them are not available. It is the result of selection, optimization, and compensation mechanisms at the individual or cultural level that older persons do not necessarily show a decline in the performance of certain tasks usually executed by young people. Not only is this true, but older people can also exhibit elevated levels of a highly specialized performance in the professional field and in solving existential problems (^{Neri, 2007}).

The concept of life purpose evolved together with the theory of successful aging and is considered a behavioral potential that favors health and well-being (^{VanderWeele et al., 2020}). In the literature, this concept is addressed as a factor that maintains quality of life in individuals over 60 years of age. Objectively, this variable is related to characteristics that favor attitudes and a sense of purpose such as motivation, goal management, and self-care, which are directly linked to successful behaviors during human development and self-regulation (^{Vander Weele et al., 2020}).

^{Reich and collaborators (2020)} conducted an ethnographic review comprising the period from 2010 to 2020 on the concept of successful aging in several countries. In open-ended interviews with older adults, asking what successful aging meant to them, the researchers did not identify any relevant studies that addressed the topic in regions such as Africa, South America, Eastern Europe, North Asia, or the Pacific Islands. The answers varied but generally focused on topics such as social engagement, positive attitude, independence, and physical health.

The Stoic view of longevity is based on the principle of optimizing the process of aging through the constant pursuit of purpose. Rather than focusing solely on prolonging life, Stoics prioritize the dignity and meaning of this journey. This means expanding the meaning of life so that it goes beyond the individual, reaching a broader and deeper purpose (^{Lang & Rupprecht, 2019}). This approach can generate resistance or aversion to the idea of simply prolonging existence, placing meaning and the pursuit of meaning as key elements.

The preservation of dignity and of the intrinsic meaning of a prolonged existence assumes a primary role within the context of a Stoic mindset. As highlighted by ^{Lang and Rupprecht (2019)}, this approach may overcome the mere absence of chronic conditions in later life. In terms of desired lifespan, adopting a Stoic mindset can imply the ability of individuals to express an in-depth assessment not only of life itself but also of their own trajectory as it unfolds. This process may also generate reluctance or aversion to contemplating exclusively the prolongation of existence, prioritizing instead the dignity and meaning that underlie Stoic motivation. Within this context, the Stoic perspective on longevity is rooted in the principle of optimizing the aging process through the incessant pursuit of meaning. In other words, this corresponds to expanding the scope of this meaning to encompass purposes that transcend many issues (^{Lang & Rupprecht, 2019}).

In a meta-analysis comprising databases such as PubMed, Embase and PsycInfo up to June 2015, ^{Cohen, Bavishi and Rozanski (2016)} investigated the relationship between purpose in life and mortality from cardiovascular diseases. The authors concluded that a high sense of purpose is associated with a reduced risk of all-cause mortality and cardiovascular events. This finding highlights the importance of purpose in life as a protective factor for health, especially in the context of old age.

Different factors such as achieving successful aging are considered crucial and life purpose is one of the most impactful. The scientific literature corroborates that the lack of life purpose is significantly associated with functional decline in daily activities and with higher mortality of older adults (^{Tomioka et al., 2016}). Thus, promoting a purpose in life can be essential for improving quality of life and for reducing health risks of older adults.

Aspects of physical activity and purpose in life

The literature on the life purpose perspective explains that it is more costly for individuals who need physical activity the most or need to increase it to have life purposes that require healthy behavior changes, such as people at risk of chronic diseases. Thus, the application of interventions including behavior change strategies that motivate people to have new beliefs and attitudes towards healthcan be considered important (^{Kang et al., 2019}).

Yu (2022) examines the relationship between the pursuit of purpose in life and the momentary negative reactions of individuals when facing everyday frustrations. The study highlights that life purpose is not defined exclusively by the condition of being or becoming an active person over the age of 60 but involves broader and more subjective aspects. It is essential to understand that purpose in life can be achieved in different ways, contexts, and environments, which will depend on the life experiences and stories of each individual (^{Podhorecka et al., 2022}).

Studies such as that by ^{Silva et al. (2022)} indicate that older people with a strong purpose in life, possibly influenced by participation in physical activities, tend to achieve personal goals such as traveling or other objectives and exhibit better functionality in activities of daily living, in addition to greater well-being. The study also highlights the importance of an active and balanced lifestyle, including controlling the consumption of substances such as alcohol and cigarettes, to attain these goals.

According to Piggin (2019), the concept of physical activity goes beyond exercise and energy expenditure, encompassing political, social, and cultural dimensions. The traditional view of physical activity as a universal solution for public health problems highlights its relationship with social inequalities and structural barriers encountered by vulnerable populations, such as lack of access to adequate spaces and limited time due to working conditions (Piggin, 2019). The physical activity guidelines of the Brazilian Ministry of Health recommend 150 to 300 minutes of weekly moderate physical activity for additional health gains (^{Brasil, 2021}). Piggin (2019) suggests that, although important, policies must be complemented by actions that ensure equal access to physical activity, providing suitable and flexible environments for all social groups.

Various factors discussed in this review are related to purpose in life, including age, sex, educational level, income, ethnicity, and physical activity. The Guia Brasileiro de Atividade Física para a População Idosa (Brazilian Guide to Physical Activity for the Elderly Population) describes that one of the benefits of performing physical activity during aging is the stimulation of human development and well-being, contributing to living a life in full and to better quality of life (^{Brasil 2021}). A review highlighted that physical activity is an important factor for the life purpose of older people (^{AshaRani et al., 2022}), which is directly associated with successful aging, resilience, and adaptation to age-related changes (^{Carriedo et al., 2020}; ^{Choi et al., 2017}; ^{Schuch et al., 2018}).

^{Costa et al. (2020)} explain that low adherence of older adults to regular physical activity and their moderate perception of quality of life indicate the need for more effective strategies to integrate physical activity into their routine in order to obtain lasting benefits. Self-efficacy, i.e., the belief in one’s own ability to perform physical activities, plays a fundamental role in this process. ^{Ghayour, Arabshahi and Saatchian (2023)} reinforce that interventions that improve self-efficacy have a positive impact on motivation to exercise, which is essential for promoting healthy aging.

The literature also confirms that social support plays an important role in engagement in physical activity, especially in old age. ^{Paiva, Gaspar and Matos (2016)} highlight the integration of social support and self-efficacy with life purpose, creating a positive circle for maintaining the health and well-being of older adults. Furthermore, studies such as that by ^{Wickramarachchi, Torabi and Perera (2023)} indicate that physical activity exerts a positive impact on the strength, balance and functionality of older adults, suggesting that programs focused on muscle strengthening are essential to improve functional performance.

It is also difficult for people with fragile health conditions to have, for example, the self-esteem to perform physical activity, which will also require reinforcement of a more active behavior. Purpose in life is a function of goals associated with essential values, which cannot be missing in life. Thus, individuals with a greater sense of purpose are able to maintain good lifestyle changes, especially in the long term (^{Kang et al., 2019}).

The pursuit of longevity also involves living well and not just living longer. Purpose in life has been treated in the literature as a perceptive feature inherent to values, desires, and motivations in different contexts of life. Studies indicate that older people who perceive them positively give meaning to their existence, direct their actions intentionally, are happier, and perceive themselves as independent (^{Oliveira et al., 2019}).

Sense of purpose is the perception of individuals of their personal development, achievements, happiness, satisfaction, self-love, self-confidence, and motivation to live and carry out their activities of daily living. It is a health dimension that involves the sense that life has meaning and direction and that projections are and/or can be achieved (^{Ribeiro et al., 2018}).

It can thus be said that people, especially adults and older adults, who maintain a good purpose of living in different contexts of life possess essential elements for maintaining health, particularly in situations of fragility (^{Ribeiro et al., 2018}). In this regard, the sense of purpose acts as a resource of resilience against different barriers in the contexts of everyday life, especially those related to physical activity and health.

Considered a psychological resource, purpose in life can help defend and cope with certain actions and personal and environmental implications. Because they are subjective and individual, they are important for adapting to the inability to cope with different situations and mitigate adversities and stressful situations that can help in the management of the real and potential environment. Such resources can also be indicators whether extended life will be lived effectively or with frailty, pain, and dependence (^{Bandura, 2006}), especially at different stages of life.

The domain of life purpose addresses the set of behavioral actions that give meaning to life and feelings of existential fulfillment and perception of life, for example: Is life worth living with clear and positive ideals to achieve? When existential questions about the meaning of life are not satisfied, the individual develops an existential void characterized by feelings of hopelessness, boredom, aggression, and depression that can evolve into existential despair, in which there is no longer any reason to live (^{Rigoni, 2014}).

Being less aware of a purpose related to something may partially explain why some individuals do not regularly engage in healthy behaviors, including physical activity. Having a regimented life with desires, motivations, expectations of results, and goals is synonymous with self-regulatory strategies that can have many health-related benefits over the years (^{Hooker & Masters, 2016}).

The literature shows that satisfaction with past events and recurring memories directly influence the way older people evaluate their quality of life and are also associated with happiness in the present moment (^{Bishop et al., 2010}). The promotion of positive thoughts and feelings, corresponding to the psychological domain of quality of life, is directly influenced by resilience (^{Chaves & Gil, 2015}). This concept refers to the attitudes and feelings that individuals have about themselves and their existence. Resilience, in turn, impacts not only quality of life but also the meaning, direction of attitudes, beliefs, and choices related to life purpose (^{Duarte et al., 2020}; ^{Ribeiro et al., 2018}).

Resilience has been indicated as a characteristic of older people who are older than 100 years old (Yemiscigil & Vlaev, 2021). Resilient older people are more likely to have a good perception of quality of life. This perception is based on positive beliefs and attitudes towards health and old age. This is even the case of centenarians, who have low functional performance and even limitations in carrying out basic and instrumental activities of daily living, as well as comorbidities and chronic-degenerative diseases and reduced intellectual activities and sociability (Yemiscigil & Vlaev, 2021).

A prospective cohort study conducted in the city of Nara, Japan, with 1,853 participants of both sexes (43.3% women) found that older people without life projects were more likely to have perceptions of being older, to suffer from depression, and to have low income, an abnormal body mass index, a tendency to consume alcoholic beverages and cognitive problems. The same study identified that older people with lower financial income exhibited a better sense of purpose (^{Tomioka et al., 2016}).

According to Windsor et al. (2022), individuals who perceive their aging positively adapt to life changes in a more positive way, while those with a more negative perception end up avoiding goals. The authors explain that individuals with greater awareness of their aging process tend to see themselves as having potential for engagement and meaning in an active life.

A look at the issues addressed in this study transcends the biological dimension and focuses on more behavioral aspects. According to ^{Oliveira et al. (2019)}, the reflection on health should be encompassing and not articulated only in a health-disease view. It is known that affective, social, and behavioral factors protect against the development of different diseases associated with the aging process (^{Oliveira et al., 2019}).

Countries with low development indices like Brazil, especially in terms of health promotion, are overburdened in providing basic and dignified health care to the population, especially older people. The latter are considered a target population for studies related to behavior changes, such as interventions that study the relationships between life purposes and active behaviors, with individuals projecting themselves effectively throughout life and in old age in terms of positive attitudes being a health protection factor (^{Ribeiro et al., 2020}).

One aspect requires further investigation in the context of life purpose, especially in older adults. ^{Duarte, Lopes and Campos (2020)} observed that community elderly Amazonians, even in the face of adversities such as morbidities and low income and education, had a positive perception of purpose. This perception was associated with psychological well-being, self-esteem, meaning and direction in life, goal setting, personal growth, motivation, a positive outlook, and the perception of happiness and health. Furthermore, low levels of income or education did not reduce positive outcomes. Thus, the question arises how socioeconomic conditions, access to education, and income may or may not influence a positive perception of life purpose (^{Duarte et al., 2020}). That is, there is still an aspect in the literature that requires further investigation and discussion: the issue of financial income, which may positively or negatively influence life purpose.

Finally, a limitation of this study is that a systematic review or meta-analysis was not carried out, which would permit a more in-depth and quantitative analysis of the evidence on the topic. Nevertheless, this study used terms such as “successful aging”, “life projects” and “physical activity” on the Capes portal, covering review and intervention articles published between 2016 and 2023, in addition to books, scientific articles and public policy documents using significant criteria for inclusion and full-text analysis. However, the lack of a systematic analysis may limit generalization of the results and the identification of possible gaps in the literature with greater rigor. Nevertheless, the study indicates paths for further research, whether cross-sectional or experimental.