This five-year plan for a MOSAIC K99/R00 Postdoctoral Career Transition Award will equip Dr. Erica
O’Brien with essential knowledge and skills to help launch her career as an independent scientist in health-
focused aging research. This qualified candidate seeks to focus her research program on understanding the
psycho-social and social cognitive determinants, multi-factorial pathways, and temporal dynamics underlying
lifelong engagement in health-promoting behaviors and activities. The career development plan involves
scientific training at Pennsylvania State University’s College of Health and Human Development under the
mentorship of world-renowned experts in ecological momentary assessments, physical activity, aging/adult
development, and health behavior research. The proposed training will supplement Dr. O’Brien’s existing
background in studying age-related differences in cognitive engagement and in using diary designs with a
foundation in intensive longitudinal methods and technologies as well as in health behavior research.
Physical activity (PA) serves as an important behavioral pathway to delayed functional decline, disease,
and mortality as well as to improved quality of life and psychological well-being in older age. Yet, many people
do not obtain the recommended levels of PA, with insufficient PA being more likely in older adults. Existing
studies increasingly indicate that people who believe that low PA reflects an expected and inevitable part of the
aging process report lower levels of PA engagement, but the pathways explaining this relationship are unclear.
Whereas theories of aging suggest that negative self-views of aging (NS-VOA) adopted earlier in life become
internalized and self-fulling later in life, health behavior theories emphasize the lack of motivation to engage in
PA and poor self-regulation of PA behavior as driving forces. Guided by these ideas, the proposed research
uses an intensive within-person approach to characterize the relationship and underlying mechanisms between
PA and NS-VOA as they unfold in daily life.
K99 Years 1 and 2 will use existing data to address Aims 1 and 2. Aim 1 will characterize the extent of
within-person variation in NS-VOA, testing whether NS-VOA vary significantly on four timescales: years, weeks,
days, and moments (i.e., within-days). Aim 2 will examine the association between NS-VOA and PA on daily and
momentary timescales. It is hypothesized that PA engagement will be lower on occasions when NS-VOA are
higher than usual, with stronger relationships for higher (vs. lower) intensity PA and when device-based (vs. self-
reported) PA are used. Aims 1 and 2 are novel, within-person assessment contexts important for understanding
fast-acting relationships and underlying mechanisms. R00 Year 3 will collect and analyze new data for Aim 3 to
test whether NS-VOA act through motivation and self-regulation factors to influence PA on daily and momentary
timescales. This work will inform preparation and submission of an R-grant (R00 Years 4 and 5) that focuses on
prevention and intervention to increase older adults’ PA at key times when NS-VOA may impair PA engagement.