Introduction

The worldwide interest in aging science continues to grow due to the increasing numbers of Baby Boomers entering retirement. The implementation of health research into longevity and health span is extending the capabilities of older adult populations by promoting physical, social, spiritual and cognitive activity, allowing them to maintain autonomy, independence and in some cases, restore physical functioning and robustness (Cochrane et al., 2016; Marzetti et al., 2017).

Society’s understanding of life-long physical activity to combat disease, disability and dependence weighs heavily as researchers continue to divulge the implications of physical activity (PA) and old age (Marzetti et al., 2017; Vaughan et al., 2016). Regular PA distances the process of requiring institutionalization in old aged-care facilities, lengthening the time as community-dwellers and/or ambulators (Bauman et al., 2016; Vaughan et al., 2016). As a result, the social implications offered to older adults and family support reduce the impact of depression and loneliness, producing significantly fewer functional limitations in daily movement (Prieto-Flores et al., 2011; Vaughan et al., 2016). Unfortunately, the ability for an older adult or “oldest old” (> 80 years) to live independently is becoming an unreachable notion (Cochrane et al., 2016), as worldwide trends demonstrate that PA was reduced in more than a quarter of the world’s population in 2016 (Guthold et al., 2018). Referrals to old age-care facilities are becoming utilized as our society’s new ‘normal’ process of aging. The United States has seen a 35% increase in prevalence of disability of ages 65 and older associated with overall decreases of PA (Vaughan et al., 2016). Consequently, these statistics represent a growing health burden in the aging population, highlighting the importance of PA for society. On the contrary, associated benefits of PA are known to improve self-efficacy, motor control, balance, cognitive health, psychological health, quality of life (QOL) (Awick et al., 2017; Bauman et al., 2016) and mitigate the onset of sarcopenia, frailty, cognitive decline, mental health illnesses, and incidences of falls and delayed mortality (Awick et al., 2017; Elavsky et al., 2005; Marzetti et al., 2017). These findings establish a demand for research into regions of the world that have adapted to life-long PA, potentially serving as a contributing factor to extreme longevity (Deiana et al., 1999; Pes et al., 2013; Poulain et al., 2021).

To date, there has been no research investigating the modes and frequencies of PA engaged by the “oldest old” (> 80 years), nonagenarians (> 90 years), centenarians (> 100 years) and supercentenarians (> 110 + years) populations in Blue Zone regions that are living longevous and independent lives. However, emergence of anecdotal, observational evidence and more recent studies examining culture, environment, and lifestyle have fascinated world leaders in longevity sciences. There are five geographical regions that surpass general civilization’s expectations of old age and do so remarkably by delaying the appearance and effect of disease and disability (Poulain et al., 2021). These regions termed “Blue Zones” include Loma Linda, CA, USA; Nicoya, Costa Rica; Sardinia, Italy; Ikaria, Greece; and Okinawa, Japan (Beuttner & Skemp, 2016; Poulain et al., 2021). How these centenarian populations are thriving in a world marred by chronic disease and age-related decline have been investigated. In these investigations, the Blue Zones have been categorized by their unique commonalities of the impacts that geographic isolation of the land, terrain, environment, and culture have on their lifestyles and health status (Poulain et al., 2021).

Although studies have been conducted with a primary focus on the following domains: sociodemographic, anthropology, psychology, epidemiology, nutrition, and genetics, there remains a paucity of literature investigating the types of PA, movement and hobbies participated in by centenarians (Pes et al., 2018; Poulain et al., 2021). Amongst the extant literature, it is suggested that centenarians engage in continuous movement throughout the day, which could cause challenges for extracting all modes, durations, and frequencies of activities in a 24-h period (Pes et al., 2018). These are the limitations of the several observational study methods utilized to analyze Blue Zone populations resulting in literature gaps amongst the modes and influences of PA. To advance the knowledge on this topic, more research is deemed necessary to explore the activity engagement of the oldest old demographic including the geographical and cultural influences of movement within each Blue Zone.

Insight into types of physical activities may help researchers develop optimal movement sequences and models that can be easily undertaken by aging adults. Furthering this knowledge could be used as advice from health practitioners to their patients to improve overall health and quality of life. This review may prompt researchers to expand their investigation regarding robust centenarians and their forms of physical activity in each Blue Zone. This could result in fostering a mastery of longevity and advancing preventative frameworks of early morbidity and disability of older adults. Therefore, this review was guided by the following research questions: 1) What are the modes of PA that predominate the Blue Zone? 2) How does geography and culture influence PA within the Blue Zones?

Objective

To the author’s knowledge, there are no current publications being explored or conducted, specifically regarding the types of PA engaged in by centenarians in each Blue Zone, including the different influences such as environment, culture, social community, work, and agriculture. The objectives of this investigation are to: 1) explore modes of PA that predominate the Blue Zones and 2) determine the environmental and cultural influences on physical activity in the Blue Zones.

Methods

Protocol and Registration

A protocol was developed based on the PRISMA Extension for Scoping Reviews (PRSMA-ScR): Checklist and Expansion (Tricco et al., 2018). Protocol registration was submitted to Open Science Framework (OSF) on 08/12/2021, where the registration information can be accessed via the OSF website (https://doi.org/10.17605/OSF.IO/RA5M8).

Eligibility Criteria

The Population-Concept-Context (PCC) framework from the Joanna Briggs Institute (JBI) Reviewers manual, were the building blocks for the eligibility criteria (Peters et al., 2020). These included studies containing categorized values between age of population, the geographical region and data for  > 80 years of age groups relating to physical activity or environment. If a study examined different regions, it had to include categories specifying values for an individual Blue Zone or signified data separate from the other regions to be an eligible study.

Exclusion criteria were agreed upon on the premise of maintaining integrity of the scoping review by excluding case study papers, and all literature reviews. To maintain literature with an independent and ambulatory demographic, exclusion of old age-care facility settings was applied. Articles that were written in other languages than English or did not have accessible full text were automatically excluded.

Population

Population demographics included any individual that are amongst the oldest old and/or octogenarians (> 80 years), nonagenarians (> 90 years), centenarians (> 100 years), and super centenarians (> 110 + years) that are living independently in the defined Blue Zones.

Concept

There were four main concepts studied in the regions of the five Blue Zones: 1) physical activity, 2) environment, 3) centenarians and 4) longevity. Blue Zones were defined as geographically identified areas with high concentrations of centenarians that have reached the age of 100 years at a rate 10 times greater than the United States (Beuttner & Skemp, 2016). Each region had commonalities that promoted physical activity, which included landscape, community, social, and occupational environments (Beuttner & Skemp, 2016; Panagiotakos et al., 2011; Poulain et al., 2021).

Physical activity was coined as an umbrella term defined as any voluntary movement elicited by the musculoskeletal system that required energy expenditure (Dasso, 2019). Blue Zone centenarians were defined as being 100 years and older, studies pertaining to Blue Zones have examined octogenarians or oldest old (80 and over) and nonagenarians (90 and over), while longevity included long-lived persons starting at the age of 90 years (Legrand et al., 2019; Panagiotakos et al., 2011; Poulain et al., 2021). Considering the following, this review explored the 80 and over demographic in Blue Zones due to the delay of age-related chronic disease commencing with the oldest old (Willcox et al., 2006).

Context

Contextual factors of the study included all periods of time and geographical locations inclusive of the five defined Blue Zones; Ikaria, Greece; Okinawa, Japan; Sardinia, Italy; Nicoya Peninsula, Costa Rica; and Loma Linda, California. Additionally, centenarians within the Blue Zones, both male and female who have maintained independence, autonomy, and were active participants in their community were included in the current study. Studies including populations of centenarians that were cared for in an age care facility were excluded.

Information Sources & Search Strategy

An initial rapid search was completed by three researchers (CH, RD and MH) on the date of 03/11/2021, through PubMed to conceptualize and develop key terms, research questions, population, concepts, and context of this review. The preliminary search through five selected databases (PubMed, Web of Science, CINAHL, ProQuest Dissertation & Theses Global, and Google Scholar) was completed to capture 10 data-rich articles to correspondingly develop a search strategy that would result in inclusion of these specific references. Multiple search strategies were designed before the research team decided on the final strategy, which included three out of the four main concepts. ‘Environment’ was not inserted into the search strategy as the search results produced irrelevant references in the databases, so exclusion of the term was deemed appropriate (see Table 1). The Bond University Librarian was consulted to refine the search strategy and provided guidance on formatting to translate the search strategy into the databases. The use of Yale MeSH Analyzer improved the search precision to pull key terms from relevant articles to insert into the search strategy (Hocking, 2017). Following the consultation and a meeting with the research team, the following terms were added: “longest lived” and “motor activity,” as both terms associated with the aims of the study and made the search strategy more concise. Guidance with modified search strategies for ProQuest Dissertations and Theses Global, and Google Scholar databases was also provided to exclude the “MeSH terms” function and to use the “Title/Abstracts” instead. The following search strategy for ProQuest Dissertations & Theses Global and Google Scholar were entered directly into the databases and are included in the appendices (Appendix A) along with the search strategies for each database. The most recent search strategy was conducted on Dec 1, 2021, identifying references in each database and screening for new publications. The sum of articles identified did not change (see Table 1, and sum of articles in Table (7) included in the Appendix).

Table 1 Search terms used to develop the search strategies with the list of databases used
Full size table

Study Selection

The final search results were exported into EndNote (Clarivate Analytics, version 20, 2020) to create a reference library that was exported to Systematic Review Accelerator (SRA) for removal of duplicate articles by one reviewer (RD) (Clarke et al., 2020). Screening of articles was completed by two reviewers (CH and MH) independently, reviewing the title and abstracts against the eligibility criteria. The screening process was finalized in Disputatron (SRA) to settle differences in results with a third reviewer for consolidation (RD) (Clarke et al., 2020). Full texts were obtained by one reviewer (CH) and additional exclusion between each reviewer was completed based on the agreed methods during screening to maintain consistency. Any uncertainty was referred to the research partners (MH and RD), including a collective decision made on the excluded articles. The complete study selection process was documented in the PRISMA-ScR flow diagram.

Data Extraction

Following inclusion by the eligibility criteria, categories entailing concepts and themes were created in tables on Excel by the research team. The initial data extraction table items were formed by the research team (MH, RD, and CH). A piloted data extraction process took place with a research supervisor (KKS) for guidance and refinement of categorization, themes, and main findings. Data extraction was processed by two reviewers (MH and RD) with extraction into individual Excel spreadsheets. The research team cross-checked the results to consolidate the findings. A third reviewer (CH) was referred to, to warrant consensus and contribute to data collection of missing data.

The key items for data extraction consisted of study characteristics (e.g., author/year of publication, study design, study aims/objectives, level of evidence and setting), participant characteristics (e.g., location/country, sample size, age, and sex) and PA data characteristics (e.g., outcome measures, outcome values, types of physical activity, environment/location of the PA, frequencies of PA, and activity participation sample size), and the main findings. Additional items were documented for qualitative studies, excluding outcome measures and outcome values. The items included phenomena of interest, methods, methodological frameworks, themes, descriptions, illustrations, and main findings.

The current scoping review identified knowledge gaps through conceptualization and mapping of relevant research. Determining the quality of the research included did not align with the current aims of the review, so a critical appraisal was not required. While a formal evaluation of the quality of individual study types was not necessary, each study’s level of evidence was determined based on the National Health and Medical Research Council (NHMRC, 2009) evidence hierarchy consistent with the study type and methodology employed. Levels of evidence for prognosis were selected, as the aim of this study entailed analyzing the forecast of achieved benefits over time while the “oldest old” implemented active lifestyles (Hoffman et al., 2013). Level IV in the hierarchy table was modified to include cross-sectional study designs, consistent with the levels of evidence for aetiology, as it was included in the lowest level along with case series (McNair & Lewis, 2012). The addition was considered to draw strengths in relevant studies involving ‘prevalence’ of factors that were concluded in cross sectional study designs (Hoffman et al., 2013).

Data Synthesis

Once data was extracted, the collected data was divided in terms of general study characteristics, study design characteristics, quantitative data, qualitative data, and prevalent modes of PA within the studies. Study design characteristics included the total number of studies examined per Blue Zone, the levels of evidence, study designs utilized, settings/context, author and year. Additionally, general study characteristics categorized year of publication, country of publication, study design, and population studied.

Themes were quantitatively categorized by: 1) outcome measures, 2) outcome values, 3) modes of PA, 4) frequencies of activity and 5) the main findings. When extracting the outcome measures and values, it is important to note that some authors administered various measurement tools resulting in heterogeneous outcome values. Therefore, the individual measurement tools were not categorized, rather, they were broadly categorized as “outcome measures” and are contained within the appendices (Appendix B). The two qualitative studies presented the following: 1) descriptions of themes and/or participants, 2) illustrations of cultural and environmental influences, 3) main findings of modes and/or frequencies of PA.

To represent the prevalence of modes of PA that were reported, activities were categorized into the following groups: 1) agricultural activities (e.g. gardening, farming, shepherd work), 2) in-home activities (e.g. house-keeping, basho-fu weaving), 3) outdoor hobbies (e.g. sports, social/cultural activities, nature engagement, swimming, horseback riding, and dancing), 4) walking (e.g. hiking in the mountains), 5) other labour occupations (e.g. sailors, fishermen, craftsmen, tradesmen, and coalminers), and 6) n/a (e.g. no modes of PA identified in reference). These themes were included in a visual portrayal per individual activity to provide an understanding of prevalent modes reported in studies. Sample sizes of specific activity engagement by participants were extracted from all studies, but only obtained by eight studies in total. In cases where sample sizes were not reported, two processes were followed: 1) if sample size percentages of activity participation were reported, the activity sample size (n) was calculated by multiplying the percentage (%) by the overall sample size (N) in the study, 2) if the percentages for participation of individual activities were not reported, sample sizes of that that study were not included in the synthesis of percentages of activities engaged in low, moderate and high intensity activities. Considering this, there were limitations in summarizing the sample size population percentages and identifying the most prevalent mode of PA relative to the sample sizes due to each study not consistently reporting the same activities throughout. As an alternative, each activity was categorized into three levels of intensities: low, moderate, and high.

The following activity was categorized as low intensity: Basho-fu weaving which was described as the most labour-intensive activity as it was a continuous task completed throughout 20 days, however, it involved hand dexterity, fine gross motor skills and precision (Willcox et al., 2007b). Moderate intensity activities were categorized in studies as the following: swimming, dancing and walking that were identified as modes of aerobic moderate intensity (Legrand et al., 2021); shepherd work had been labeled as constant and continuous energy expenditure walking long distances in the mountainous terrain (Pes et al., 2013); outdoor hobbies and nature engagement are broader terms that have been categorized as moderate intensity activities relating to swimming and gardening outdoor tasks using both upper and lower limbs which were identified as such by Legrand et al. (2019) and Nicklett et al. (2016); housekeeping pertaining to household chores that involve vacuuming, mopping, washing windows, etc., have met the metabolic equivalent value of 3.0 equating to moderate intensity activities (Manini et al., 2006). High intensity was categorized between the remaining activities, farming, and other labour occupations. Pes et al. (2013) suggested farming to be labouring in concentrated periods and described other labour occupational demands in similar terms as farming.

Results

Selection of Sources of Evidence

Reference identification, screening, and eligibility processes enforced in this scoping review can be viewed in the PRISMA flow diagram (Fig. 1). Through a multi-database search, a total of 236 articles were identified through PubMed, Web of Science, ProQuest Dissertations & Theses Global, CINAHL, and Google Scholar. There were no other articles identified through additional sources. Following the removal of duplicates, 169 articles were screened by two reviewers. After viewing titles and abstracts against the eligibility criteria, consensus was made to exclude 127 articles. Exclusion was made on the grounds of articles not including PA values categorized for participants > 80 years old, not extracting PA data, areas not in Blue Zone regions, not written in English, and any study designs (literature review and full text) not available. Retrieval of full texts were conducted for 42 articles, with 24 articles being further excluded due to their inaccessibility or lack of eligibility, leaving 18 articles in total to be studied in this review. This comprised 16 quantitative and two qualitative studies. Exact sum and process of selection can be found in the PRISMA flow diagram (Fig. 1).

Fig. 1
figure 1

PRISMA-ScR flow chart. Source: Tricco, A. C., Lillie, E., Zarin, W., O’Brien, K. K., Colquhoun, H., Levac, D., Moher, D., Peters, M. D., Horsley, T., Weeks, L., & Hemple, S. (2018). PRISMA extension for scoping reviews (PRISMA-ScR): checklist and explanation. Annals of Internal Medicine, 169(7), 467–473. doi:10.7326/M18-0850

Full size image

Study Characteristics

Of the 18 articles that were included, all were reviewed for data extraction and synthesis. A summary of the study design characteristics can be found in Table 2, displaying the number of studies explored for each Blue Zone, the methods utilized and the levels of evidence according to the study type.

Table 2 Study Design Characteristics
Full size table

General study characteristics were extracted to provide a synthesized understanding of periods of publication, countries of publication, study designs and populations studied (Table 3). Analysis of these themes was drawn from the increased number of studies in certain categories, with a significant portion of studies conducted in the last five years (Fastame et al., 2018; Legrand et al., 2019, 2021; Madrigal-Leer et al., 2020; Nieddu et al., 2020; Pes et al., 2018, 2020, 2021; Spencer-Hwang et al., 2018) and being primarily of a cross sectional design and published in the United States (Chan et al., 1997; Legrand et al., 2019; Panagiotokos et al., 2011; Pes et al., 2018, 2020; Spencer-Hwang et al., 2018; Willcox et al., 2007b, 2008) with cross-sectional study designs (11 out of 18, level IV evidence) utilizing questionnaires were the most common research tool (Akisaka et al., 1996; Chan et al., 1997; Deiana et al., 1999; Fastame et al., 2018; Legrand et al., 2019; Legrand et al., 2021; Madrigal-Leer et al., 2020; Nieddu et al., 2020; Panagiotakos et al., 2011; Pes et al., 2013, 2018). Populations that were investigated most commonly were Okinawan resident centenarians (Akisaka et al., 1996; Chan et al., 1997; Willcox et al., (2007a)) and centenarian residents of municipalities in Sardinia (Deiana et al., 1999; Pes et al., 2013; Poulain et al., 2004).

Table 3 General Study Characteristics
Full size table

Summary of Outcome Measures and Findings Across Study Themes

Assessment measures of Blue Zone participants found in the Appendix B reveal the level of function of the “oldest old” (i.e., those over 80 years of age) in Ikaria, Sardinia, Okinawa, Nicoya through outcome measures and values (Akisaka et al., 1996; Chan et al., 1997; Deiana et al., 1999; Legrand et al. 2019, 2021; Madrigal-Leer et al., 2020; Nieddu et al., 2020; Panagiotakos et al., 2011; Pes et al., 2018, 2020, 2021; Willcox et al., (2007a, 2008). The outcome values include the following: Activities of Daily Living (ADL) scores, Instrumental Activities of Daily Living (IADL) scores, Basic Activities of Daily Living (BADL) scores, International Physical Activity Questionnaire (IPAQ) results, and grip strength. Whereas frequencies values in Table 4 represent a summarization of motor activity index values, MET measurements, durations, intensities, volumes, and levels of physical activity engaged in by the oldest old. The main findings indicate that the frequencies of PA and moderate to high levels of physical functioning (Akisaka et al., 1996; Chan et al., 1997; Deiana et al., 1999; Legrand et al., 2019, 2021; Madrigal-Leer et al., 2020; Nieddu et al., 2020; Panagiotakos et al., 2011; Pes et al., 2018, 2020, 2021; Willcox et al., 2007a, 2008) enable the oldest old to engage in long-term community activities that result in moderate to high levels of PA (Legrand et al., 2019, 2021; Panagiotakos et al., 2011; Pes et al., 2013, 2018) and moderate to high levels of autonomy and independence (Akisaka et al., 1996; Chan et al., 1997; Legrand et al., 2019; Neiddu et al., 2020; Pes et al., 2018, 2020, 2021; Willcox et al., 2008).

Table 4 Frequencies of modes of PA that were reported for the oldest old to engage in their lifestyles or were discovered by measured assessments
Full size table

Pertaining to the analysis of specific activity frequencies engaged in by participants, there was a high heterogeneity in values limiting overall population comparison. However, data was summarized from six quantitative (Fastame et al., 2018; Legrand et al., 2021; Madrigal-Leer et al., 2020; Pes et al., 2013, 2018, 2020) and two qualitative studies (Spencer-Hwang et al., 2018; Willcox et al., 2007b). In relation to agricultural activities, the majority of oldest old Sardinians reported gardening 1–4 days per week, with 1.7–2.3 hours on average allocated for outdoor hobbies per week (Fastame et al., 2018), while centenarians working as shepherds would walk a mean distance of 12.4 km to and from work and on an average slope of 15.2% daily (Pes et al., 2013). Parameters around walking frequency values that were not directly linked to a specific activity included the Sardinian ≥ 90 years of age engaging in 12,110 steps per day for men and 12,799 steps per day for women on average (Pes et al., 2018) and engaging in PA or walking ≥ 3 times per week (Pes et al., 2020). This is relative to the percentage of participant’s total energy expenditure (TEE) of  ≥ 3 METs which is the corresponding threshold for moderate physical activity which exceeds 40% of participants (Pes et al., 2018).

A qualitative summary of studies is presented in Table 5, depicts the activities within culture and environment that illustrates the relationships between hobbies, work and outdoor activities. The illustrations provided by Loma Linda centenarians introduce themes of resiliency factors, kinetic lifestyle, nature engagement, and resting reset. Specific activities that were reported include daily walks for 2–3 hours to school or around the community, dusk-to-dawn activities, farming, outdoor activities, horseback riding, and gardening. “Sabbath afternoon” involved one weekly day of “rest” where participants would engage in enjoyable lower intensity activities in contrast with their more labouring weekly activities (Spencer-Hwang et al., 2018). The following is an illustration expressing PA established early in life and had 100% agreement of the following statement that reported that.

“Going to school consisted of walking 2 miles… We spent a lot of time in nature, and [we would go] up in the mountains and swim in the lake… There was always a place to go outside” (Spencer-Hwang et al., 2018).

Table 5 Qualitative data representing participant illustrations and main findings of physical activity engagement
Full size table

The illustrations in Table 5, of oldest old women living in the Okinawan region reflect, that despite their age, they each engage in Basho-fu weaving and have done so throughout their lives. Basho-fu weaving, also known as, spooling was categorized with the in-home activities as a low intensity activity that is one of the most labour-intensive activities, in which women will spool for 20 days until completion for either income or as a hobby. The women also describe the detail and fine motor skills it takes to complete spooling, which is the one thing they believe keeps them sharp and still alive (Willcox et al., 2007b). Information about the oldest old men in Okinawa was not provided. The following as an illustration of an Okinawan woman in her early 80’s that goes by, Toshiko Taira was quoted saying that.

“There was one year when we made up to 100 rolls of [textile] material” (Willcox et al., 2007b).

Contrasting data on durations of rest was represented to provide an alternative understanding of the Blue Zone population’s continuous movement throughout the day. In contrast with the PA continuous scores (average 1533 MET min/week) reported by Legrand et al. (2021), the average time spent sitting per day for Ikarian residents ≥ 90 years of age is 90 min per day. Similar results with a different form of measurement were reported for the Sardinian participants ≥ 90 years of age regarding productive rest. The total daily resting time was measured by the participant’s duration of night’s sleep and time spent in supine in the waking day, which resulted in only 8.5 hours for men and 7.4 hours of total daily rest on average out of a 24-hour period (Pes et al., 2018).

Modes of PA reported in each study per Blue Zones region are synthesized in Table 6, along with the categorized activities, including a categorization for studies that did not specify modes of activity. The most common mode of PA found across 12 studies was agricultural activities (Fastame et al., 2018; Nieddu et al., 2020; Legrand et al., 2019, 2021; Panagiotakos et al., 2011; Pes et al., 2013, 2018, 2020, 2021; Poulain et al., 2004; Spencer-Hwang et al., 2018; Willcox et al., 2007b), whereas, seven studies reported no specific modes of PA (Akisaka et al., 1996; Chan et al., 1997; Deiana et al., 1999; Madrigal-Leer et al., 2020; Nieddu et al., 2020; Willcox et al., 2007a, 2008). The prevalent modes of PA that are represented in the included studies were synthesized for visual analysis in Fig. 2, including the number of studies that reported a mode of PA and the corresponding Blue Zone. Throughout the studies conducted on Sardinia, four studies reported agricultural activities (Nieddu et al., 2020; Pes et al., 2018, 2020; Poulain et al., 2004) and four studies reported farming as predominant modes within the Sardinian literature (Pes et al., 2013, 2018, 2020, 2021).

Table 6 Summary of prevalent modes of physical activity in Blue Zones referenced in studies
Full size table
Fig. 2
figure 2

The prevalence of modes of PA in Blue Zones that are identified in each study, including the number of studies that did not identify a mode

Full size image

Due to cases of participants reporting to engage in more than one activity, a population percentage was not able to be synthesised with activity sample sizes, however, Fig. 3 includes the percentage amount of the predominant intensity that is engaged in by the oldest old. It is significant to note that more than 60% of activities engaged in by the Ikarian, Sardinian and Loma Linda’s regions are moderate intensity activities (Fastame et al., 2018; Legrand et al., 2019, 2021; Panagiotakos et al., 2011; Pes et al., 2018, 2020; Spencer-Hwang et al., 2018), while Okinawan centenarians reflect that 83% of their activities engaged in are low intensity activities (Willcox et al., 2007b). Considering Nicoya studies did not provide activity sample sizes, nor a mode of PA, an activity intensity synthesis could not be completed for this region.

Fig. 3
figure 3

The engagement prevalence of low, moderate, and high intensity activities overall and for each individual Blue Zone identified in eight studies. Note a) In Ikaria, 68% of the activities engaged in were moderate intensity activities (Legrand et al., 2019, 2021; Panagiotakos et al., 2011). b) In Okinawa, 83% of activities engaged in were low intensities activities (Willcox et al., 2007b). c) In Sardinia, 93% of activities engaged in were moderate intensity activities (Fastame et al., 2018; Pes et al., 2018, 2020). d) In Loma Linda, 67% of activities engaged in were moderate intensity activities (Spencer-Hwang et al., 2018). e) Overall, throughout Ikaria, Okinawa, Sardinia and Loma Linda, 81% of activities engaged moderate intensity activities (Fastame et al., 2018; Legrand et al., 2019, 2021; Panagiotakos et al., 2011; Pes et al., 2018, 2020; Willcox et al., 2007a, b; Spencer-Hwang et al., 2018)

Full size image

Discussion

Key Findings

Throughout eighteen papers in this scoping review, there are significant findings across the five Blue Zones. Findings in this current scoping review consolidate the following for the first time in research: 1) Overall, centenarians are performing consistent and continuous movements daily that are predominantly moderate intensity activities, 2) their modes of PA are influenced by environment, geography, and culture. The main findings of our study conclude that the homogeneous environment in Blue Zones creates a demand for living a traditional lifestyle. For example, walking to commute, working labour-intensive occupations, participating in outdoor hobbies, and navigating complex terrain with constant exposure to uneven surfaces.

By maintaining traditional lifestyles, many of the Blue Zone regions rely on traditional economic activities that are centered around highly physical occupations such as farming, shepherd work, and agriculture (Pes et al., 2018, 2020). Pes et al., (2013) highlights that shepherd work was the most common occupation in the Sardinian Blue Zone region and the average daily walking distances of 12.4 ± 7.8 (km) at an average slope of 15.2 ± 6.6 (%) is demanding and most likely apply to shepherd workers in these mountainous regions. This type of physical occupation is considered moderate intensity that is maintained constantly throughout the year. This would involve walking long distances up and downhill on steep and narrow paths (Pes et al., 2013).  Whereas past researchers have found that only 6 % of Australian workers, 65 years and older, are full-time and 5% are part-time workers (Foskey et al., 2005). In parallel to centenarians working beyond the expected age of retirement, the Blue Zone populations are showing a low level of rest throughout the day. Legrand et al., (2021) reports that nonagenarians (90 yrs. and older) in Ikaria, Greece show remarkably little time spent sitting (minutes/day): 90 ± 120 (males), 60 ± 240 (females). This is a significant finding as prior research revealed that participants > 60 years of age spent between 5-9 hours sedentary per waking day; where these adults reported 3.3 hours in leisure sitting and 3.3 hours watching T.V (Harvey et al., 2015). The continuous activity, work life, and total rest time in Blue Zone centenarians was an unexpected finding in this scoping review. This pattern of results reflects the predominantly moderate levels of physical activity preformed throughout the day and is exceeding The American College of Sports Medicine (ACSM) recommendations of >30 mins moderate intensity exercise for ages 65 years and older (Nelson et al., 2007).

The lower socio-economic status found across all Blue Zones reflects the labour-intensive occupations and the high levels of PA engaged in by centenarians (Legrand et al., 2019, 2021; Nieddu et al., 2020; Wilcox et al., 2007b). These findings are interesting as previous research associate low socioeconomic status with health risk behaviours in older adults, however, does not specify whether this applies to rural areas or cities (Shankar et al., 2010). Health risk behaviours consisted of smoking, alcohol consumption and low levels of physical activity, where the combination of all three is high (Shankar et al., 2010). This has the opposite effect on the Blue Zone population as low socioeconomic status and traditional lifestyle drive continuous PA through work life and hobbies (Pes et al., 2013).

While an interpretation was provided on the continuous levels of physical activity, the environment and cultural influences of these Blue Zone regions play a key part in centenarian’s movements through physical occupations, commuting, and leisure-time primarily outdoors. Each Blue Zone region is in a geographical location that is isolated yet condensed with endless opportunity for community members to be encouraged to engage in the outdoors (Pes et al., 2018; Spencer-Hwang et al., 2018). It can be hypothesized that the nature of their small communities, and advanced social and cultural networks that provide a safety net is a significant factor that allows the oldest old the prospect of being outdoors. A study conducted by Tucker-Seeley et al. (2009), reports on the perceived safety of an older adult’s neighborhood as a barrier for engagement in leisure-time physical activity. In addition to perceived safety, the following were shown to determine the participation in outdoor PA for older adults: 1) pedestrian infrastructure, 2) access to facilities, 3) aesthetics and 4) environmental conditions (Moran et al., 2014). Interestingly, amongst these factors such as pedestrian infrastructure, which includes sidewalk quality, maintenance and obstacles, the Blue Zone region’s infrastructures are not kept to the same standard. Although, in Western society, the street and sidewalk quality may instill motivation and ease the fear of falls (Moran et al., 2014), however, the quality of walkways is not the reality of these small cobble-stoned villages in often mountainous regions (Legrand et al., 2019, 2021; Pes et al., 2013; Poulain et al., 2004).

Limitations

Considering the high heterogeneity of values and tests measured across all studies included in this scoping review, there were limitations in synthesizing comparative representations and statistical summary. While a range of different activities were reported in each study, a comparative population summarization was not able to be synthesized due to the potential of underrepresenting certain activity populations. Exclusively, the studies investigating the Nicoya population did not report modes of physical activity, despite referring to lifestyle practices of participants. This can be attributed to the limitations of this study’s inclusion criteria. An article would still be included based on referring to environment and physically active lifestyles, without specifically referring to the modes of PA engaged in. This resulted in the inclusion of multiple studies that did not provide modes of PA but offered other supplemental information. Another drawback was the population sizes for Blue Zone studies with reported modes of PA, such as, Loma Linda, and Okinawa. The overall conclusion and findings of these two regions potentially contain skewed data as there would be an overrepresentation of the specific activities reported in the Loma Linda (Spencer-Hwang et al., 2018) and Okinawa study (Willcox et al., 2007b). Lastly, this scoping review was not able to draw the conclusion that PA correlated with longevity, as this would require comparative national health data, and the inclusion of biological and genetic studies for comparison of other contributing factors of longevity within Blue Zones. Despite these limitations, the present study has significantly enhanced the understanding of the relationship between modes of PA, environment, and cultural influences of centenarians residing in the five Blue Zones.

Future Directions

The present study can be utilized as a tool for researchers to carry further investigation into Loma Linda, Nicoya and Okinawa regions. These were Blue Zones with either small sample sizes or did not provide specification to modes of PA, which requires further research. Future studies are encouraged to report sample sizes along with the specific mode of activity for an overall population synthesis of predominant modes of PA.

The clinical implications of this review involve providing Allied Healthcare professionals with lifestyle models that can easily be undertaken by older adults. By providing older adults with outdoor lifestyle prescriptions, Allied Healthcare practitioners can ensure activities that offer greater adherence and an increase in functional capacity compared to indoor exercise (Lacharité-Lemieux et al., 2015).

Conclusion

Overall, the centenarians in Blue Zones are a highly physically active population performing continuous and consistent movements daily, maintaining daily hobbies, and working beyond the expected age of retirement. The predominant modes of PA for centenarians across the studies included in the present scoping review were agricultural activities including, gardening, farming, and shepherd work, while the predominant level of intensity for PA was found to be moderate. The key findings represent a significant effect on PA by environmental and cultural influences of each region, where the more isolated land, extended on-foot commutes, diverse walking terrain, social life, and the maintenance of traditional meals and occupations each play an integral role of centenarian’s active lifestyles.