From this investigation of retrospectively reported PA biographies of older adults, four subgroups with different PA life course trajectories emerged from the data. Those older adults who had low amounts of PA in childhood and became increasingly active after the age of 30 were classified as increasingly active. Those who maintained high amounts of PA were classified as consistently active. Those who maintained low amounts of PA throughout the course of their life were classified as being consistently inactive. Finally, those who decreased their PA levels from childhood after age 30 were classified as decreasingly active. The consistently active classification was associated with current PA and life satisfaction; whereas being consistently inactive was negatively related to aging satisfaction, even when accounting for current PA. This research furthers our knowledge on the independent contribution of PA biographies to the variability in life and aging satisfaction in older adults. New insights include that there are types of older adults that became more active as they got older and consistently active individuals, which may be new indicators of successful aging .
The classes that emerged are in line with findings from other studies that compare an active class against more sedentary classes [7, 8]. In retrospective interviews, MacDonald et al.  found, as expected, that the number of activities and hours of PA for master athletes and sedentary older adults varied substantially across the lifespan. Likewise, we found older adults with active and inactive PA patterns; moreover, we found patterns that indicate that PA levels change throughout life. In the present study, consistent activity was positively associated with life satisfaction, which echoes literature of a positive current PA–life satisfaction relation in older adults . Additionally, our data indicates that consistently low PA levels across the lifespan is negatively associated with aging satisfaction, which supports findings showing that PA continuity was adversely related to negative views on aging in women .
In our study, PA biographies explained variance in life and aging satisfaction, even when accounting for current PA levels. Independent from current levels of PA, being physically active throughout one’s life may be an independent resource for high life satisfaction in old age. Current PA was not independently related to life and aging satisfaction in the present study when accounting for patterns in PA biographies, which further underlines the significance of PA across lifespan. Concepts such as PA identity and PA habits, which may last over extended periods of life, can help explain why having an active lifestyle may be positively related to current PA and life satisfaction [20,21,22]. Moreover, Hirvensalo and Lintunen pointed out in their review of PA across the lifespan that concepts of a lifespan theory of PA such as tracking and transitions should be elaborated upon in PA research . Tracking research highlights that early PA levels are related to PA levels in old age. Although PA patterns are relatively stable in old age, the authors argue that transitions such as widowhood and relocation into a specialized but less spacious facility such as a nursing home may be linked with reduced PA in old age .
Strengths and limitations
This study has strengths and limitations. A strength of the study is the innovative approach to PA, which incorporates a perspective of current behavior and satisfaction with a genuine lifespan perspective using a simple and intuitive biography method. Other strengths include the longitudinal design and the sophisticated statistical analyses, wherein we combined LCA with structural equation modelling. One limitation is the validity of self-reported PA levels. However, the similarities in the results of this study with other studies on the same topic show the strength of the classes developed through this survey. We do not know whether people gave accurate reports of their lifespan PA levels. Retrospectively assessed PA biographies are not equivalent to actual PA across the lifespan. The results may thus be considered to be an individual’s mental representation of PA over their lifespan. While retrospectivly reported PA is related to actual PA, it can be considered a psychological concept in its own right. Our sample was relatively active and well educated, which limits the generalizability of the findings. Future studies should replicate the class structure using a more representative sample. We were not able to link the trajectories to common life events such as transition from primary to secondary school, transition from high school to college or university, marriage, becoming a parent, or retirement [23, 24]. Nor could we link the trajectories to non-normative critical life events such as the death of a spouse or the onset of a chronic disease such as rheumatoid arthritis . These elements should be investigated in future studies.
Implications for research, policy, and practice
While our findings have shown that specific PA biography patterns relate with life and aging satisfaction in older adults, future studies should investigate whether this pattern can be replicated in different settings and subgroups of older adults. Moreover, the relationship of PA biographies with indicators of physical functioning, including specific syndromes such as frailty, would be of interest for future studies. This was not included in our study, as we focused our investigation on aging satisfaction only. Finally, more research is needed that applies tailored interventional designs. It could be tested whether certain PA biographies (e.g., consistently inactive versus decreasingly active) are more responsive to information, which are framed to their PA background (e.g., cues that describe activity as pleasure or highlight the functional value versus cues that activating past habits and benefits of an active lifestyle ).
Implications for policy and practice include the importance of childhood fitness and PA for the entire life . Although PA patterns across life appear to be stable for many individuals, tailored interventions that consider unique PA biographies may improve the effectiveness of PA promotion interventions for older adults [27,28,29]. Negative views on aging and aging satisfaction in individuals with low levels of PA across the lifespan may be target of interventions on an individual level as well as in pubic campaigns . Results from a PA intervention study in older adults have shown that positive views on aging could be changed by interventions, which, in turn, result in changes in PA in that sample . Self-reported PA biographies contribute valuable insight and enable researchers and health care professionals to gain a greater understanding of PA in older adults.