These results suggest that this high intensity volunteer program, Experience Corps—Baltimore, requiring 15 h of service per week through a full school year, may lead to substantive increases in the physical activity levels of older adults, even in the short term. These findings were particularly observed among those who, prior to service, had low levels of physical activity as defined by the Healthy Persons 2010 Guidelines.2
This pilot randomized, controlled trial observed a doubling in meaningful physical activity levels among older adult volunteers who were initially relatively inactive, while the controls reported no change. The clinically and statistically significant increase of 460 kcal/week, reported in this pilot trial, among those who initially inactive compares favorably to the 400–700 kcal/week improvements seen in other successful activity interventions.10,11
While these other trials were performed in predominantly white communities of relatively high socioeconomic status, the Baltimore Experience Corps program successfully engaged African American inner-city older adults. This model of a health promotion intervention embedded in an intergenerational volunteer program that serves children in public elementary schools therefore has the potential to increase the physical activity level of a group that is at higher risk for adverse health outcomes. The Experience Corps program in Baltimore is the first volunteer program to demonstrate increased physical activity among initially inactive participants, with an effect on physical activity that appears to be comparable to other intentional exercise trials in older adults.
Prior research has demonstrated that interventions that increase “usual physical activity” may be as effective as formal exercise programs in health promotion.6,41,44,45
This study indicates that high impact, high intensity volunteering may serve as an effective approach to increasing “usual physical activity”. By appealing to personal motivations of older adults to “give back” and make a difference for their communities and offering regular, structured activities that people are personally committed to and necessitate regular ambulation, programs like Experience Corps may circumvent barriers to activity and offer older adults more sustainable options that incorporate increased physical activity into their daily lives.
The Experience Corps was intentionally designed, through its high intensity commitment and the necessity of travel to and from and within schools 3 to 5 days/week, to lead to an increase in usual physical activity.31
These results provide additional evidence that a health promotion intervention that is embedded in an intergenerational volunteer program has the potential to increase physical activity. It further amplifies on the prior report from this pilot trial of an overall increase in activity levels and reported strength31
by delineating that those with low activity show the greatest short-term benefit. However, the sample size in this pilot study was small and the MLTAQ instrument did not specifically ask about physical activities we expected would be associated with Experience Corps volunteering: traveling to and from school three to five times a week and walking around the school and classroom and up the stairs with the students. Instead, the MLTAQ asked about “leisure time activity” (walking for exercise, household chores, exercise and recreational activities).42
However, there was a trend toward an increase in the number of blocks walked and stairs climbed by EC participants on follow-up, while there was a decline among controls. It is likely that EC participation is associated with more of an increase in ambulation-related physical activity than the MLTAQ captures.
These results also indicated that 15 h/week of service, which Experience Corps—Baltimore requires of its volunteers, does not detract from their usual physical activity outside the program. Thus, there appears to be no tradeoff of one activity for another, as has been demonstrated in aerobic activity interventions where “regular activity” decreases while aerobic exercise increases.4
Nelson's prior trial in perimenopausal women indicated that increases in strength as a result of participation in resistance training led to a 25% increase in other activities outside of the intervention. In this pilot, we have previously reported increased strength and a slower decline in walking speeds31
and, in this report, demonstrated a more than two-fold increase in time and kilocalories expended in household chores in the intervention group, compared to no change in the controls. This latter increased activity in housework, gardening, and home maintenance activities, in combination with previously reported increased strength, may support Nelson's findings, but in a substantially older and higher risk group. Older adults who become stronger due to Experience Corps participation may then take on more optional, energy, demanding activities such as increased household chores.
These findings suggest that high intensity volunteer programs, such as this intergenerational one, may have the potential to address persistent health disparities in African American and other disadvantaged older adults, while offering opportunities for preservation of activity in those already active. Healthy People 2010 identified several population groups with the lowest rates of physical activity: seniors, women of all ages, African Americans and Hispanics, people with disabilities, those with lower incomes and less education.2,46
These groups may have differential access to opportunities to be physically active.46
It has been pointed out by Adler16
that if opportunities for health promoting behaviors and community preventive services are not targeted to disadvantaged communities, health disparities will increase over time. The program in Baltimore has been successful in attracting older adults with a history of low physical activity who are from a high-risk community with lower access to health promotion and a higher burden of morbidity. In fact, 96% were African American, 84% had annual incomes less than $15,000, and there was a high prevalence of physical disability. The stipends that are provided to defray the out-of-pocket cost of this high commitment volunteering (carfare, lunches, etc), through support by local foundations and the Corporation for National Service, allowed volunteers living on fixed incomes to participate fully in Experience Corps. This suggests an approach needed to overcome barriers to being active and engaged. It is important to note further that these older volunteers are serving in schools in which 89% of the students were eligible for free or reduced cost school meals.33
Thus, mobilizing the social capital of an aging society has the potential to increase educational success of the next generation and, through this, possibly prevent or mitigate future health disparities of these students. Such mobilization, may, simultaneously, improve health and decrease health disparities in the older adult volunteers.
While the Center for Disease Control's Task Force on Community Preventive Services did not evaluate volunteer programs as an intentional physical activity intervention, four of the Task Force's strong recommendations are reflected in volunteer programs like Experience Corps. The Task Force recommended use of programs that are 1) are community-based; 2) promote individually adapted behavioral change; 3) provide social support in the community setting; and 4) offer enhanced access to activity.47
The Baltimore Experience Corps program was designed to be such a community-based intervention, in which volunteers can choose from a variety of meaningful roles based on their interests, and social networks and support are developed through training and working in teams. The elder/child relationships that volunteers in this—and other—programs develop a strong motivation for adherence to volunteering and long-term retention. Notably, Experience Corps Baltimore has only a 2–3% dropout rate during any given school year, and 80% return from 1 year to the next. 30
Finally, as noted above, the incentive stipends that volunteers receive make volunteering a viable option for financially challenged older adults. This combination of a high rate of retention and a high intensity commitment of 15 h a week provides volunteers a prolonged exposure to the health promoting behaviors. These initial findings suggest that high intensity older-adult volunteering programs should be components of the campaign that experts argue will be required to include all older adults in a society-wide increase in physical activity.48
Our study has several limitations. First, this was a pilot study. The number of volunteers was limited by available funding, and this pilot did not have the power to detect significant differences. We had not anticipated having sufficient power to measure an effect on physical activity, particularly in the stratified analyses, given the low power of this pilot trial, although differences by initial activity level were hypothesized a priori. An adequately powered randomized, controlled trial with larger sample sizes and longer follow-up time will be required to determine if there are sustained physical activity improvements over time, and to evaluate the potential for this increase in activity to contribute to health benefits and a compression of the morbidity associated with aging. Follow-up studies will also need to objectively quantitate the amount of physical activity that occurs within the volunteer program, something that we did not have the resources to do. It is possible that the modified MLTAQ is not adequately sensitive to change in activities engaged in by older adults, and it may not be the most culturally appropriate physical activity instrument for the majority of urban older adults. Additionally, while the interviewers were blinded to the subject's randomization assignment, the subjects were not, and EC participants may have expected to be more active, which could have affected the results found in Table . Also, while this model of volunteering may be attractive and effective for many older adults, it may not appeal to all older adults, and future studies should evaluate and refine social marketing messages and recruitment strategies to attract volunteers while also developing a broader array of meaningful roles that may maintain activity and attract older adults not interested in serving in schools. Finally, given the financial costs of volunteer recruitment, training and support, the sustainability of volunteer programs will benefit from evidence garnered from rigorous cost-effectiveness evaluations.
These pilot findings suggest that this high intensity model of social engagement has the potential to meaningfully increase physical activity, although a formal randomized evaluation with a longer follow-up and sample size is required to determine the sustainability and health effects of this increase in physical activity. The results of this pilot trial suggests that EC participants have increased ambulation and demonstrated increased activity in household chores, which is an Instrumental Activity of Daily Living.49
Additional research will be required to determine if older adult volunteering might be effective in promoting the maintenance of functional status as postulated in Figure 31
and thus contribute to a compression of morbidity. Physical inactivity is also a leading cause of preventable death,50
with estimated economic costs of $76 billion in 2000 in direct medical costs alone.51
To be effective, programs for volunteering by older adults will require an investment in the infrastructure required for training, volunteer support, human resources administration, and ongoing sustainability. Additionally, if volunteering as a lifestyle is to be financially viable for all retired Americans, it will require continued community and government support that includes volunteer stipends. Volunteering by older adults represents a potentially important intervention in the effort to increase physical activity. America must develop, implement and evaluate new models for retirement that support a physically active lifestyle for all older adults before the 40 million Americans in the Baby Boom generation begin to retire en masse
in 2010. The time to act is now.