Project Summary/Abstract
Adults with chronic musculoskeletal disease, such as knee osteoarthritis (OA) or back pain, are in urgent need
of an effective intervention to reduce sedentary behaviors, such as excessive sitting. Historically, interventions
have targeted physical activity via supervised exercise, but have largely ignored sedentary behaviors. Such
sedentary behaviors impact health in ways that are independent of exercise, including increased risk of
mortality, diabetes, and obesity. This is relevant to adults with chronic musculoskeletal disease who spend up
to 3.5 hours/day more in sedentary behaviors than their healthy counterparts, and where intervention targeting
sedentary behaviors has yet to be tested. However, before we can plan and implement a clinical trial, a critical
gap in knowledge that must first be filled is how much sedentary behaviors need to be reduced to have
clinically meaningful improvements in health. Surprisingly, there are no established standards to define
excessive levels of sedentary behavior, nor recommendations for how much they should be reduced.
Consequently, we are blind to what amount of sedentary behaviors should be targeted for change, and a
clinical trial would be a waste of time and resources until we first establish this. To fill this gap, we propose to
examine the relation of reduced sedentary behavior with clinically meaningful changes in pain, physical
function, and Health Related Quality of Life (HRQoL) over 2 years in a large, diverse community-based cohort
study currently in the field. The objective of this study is to use a state-of-the-art monitoring device, the
activPAL, to evaluate sedentary behaviors within 1,500 adults from the Johnston County Health Study
(JoCoHS). Our proposal will establish for the first time much-needed thresholds for targeting sedentary
behaviors that will overcome current limitations in the field for designing and implementing effective clinical
interventions that address excessive sedentary behaviors. We are specifically interested in understanding how
sedentary behavior impacts common, yet costly, musculoskeletal outcomes such as pain, strength, physical
function, and HRQoL. The results stemming from this proposal will provide essential data that is necessary for
us to plan for a future clinical trial which would then broadly inform the wider scientific community of how to
address sedentary behaviors in adults with chronic musculoskeletal disease.
